diff --git a/Mixer.cpp b/Mixer.cpp
index 2d54df1..252b825 100644
--- a/Mixer.cpp
+++ b/Mixer.cpp
@@ -82,6 +82,11 @@ void Mixer::insertSource(Source *s)
     geometry_.scene.root()->addChild(s->group(View::GEOMETRY));
 
 }
+void Mixer::deleteSource(Source *s)
+{
+    unsetCurrentSource();
+    session_->deleteSource(s);
+}
 
 void Mixer::renameSource(Source *s, const std::string &newname)
 {
@@ -290,7 +295,10 @@ bool Mixer::open(const std::string& filename)
 
 void Mixer::newSession(Session *newsession)
 {
-    // TODO : remove roots of scenes for views? done in session
+    // TODO : remove roots of scenes for views?
+//    mixing_.scene.clear();
+//    geometry_.scene.clear();
+
     // delete session : delete all sources
     if (session_)
         delete session_;
diff --git a/Mixer.h b/Mixer.h
index 6fd4d81..40312fd 100644
--- a/Mixer.h
+++ b/Mixer.h
@@ -36,6 +36,9 @@ public:
     // manangement of sources
     void createSourceMedia(std::string uri);
 
+    // TODO: deleteSource();
+    void deleteSource(Source *s);
+
     // operations on sources
     void renameSource(Source *s, const std::string &newname);
 
diff --git a/RenderingManager.cpp b/RenderingManager.cpp
index 72abc82..35b3a86 100644
--- a/RenderingManager.cpp
+++ b/RenderingManager.cpp
@@ -348,7 +348,7 @@ glm::vec3 Rendering::unProject(glm::vec2 screen_coordinate, glm::mat4 modelview)
     glm::vec3 coordinates = glm::vec3( screen_coordinate.x, main_window_attributes_.viewport.y - screen_coordinate.y, 0.f);
     glm::vec4 viewport = glm::vec4( 0.f, 0.f, main_window_attributes_.viewport.x, main_window_attributes_.viewport.y);
 
-    Log::Info("unproject %d x %d", main_window_attributes_.viewport.x, main_window_attributes_.viewport.y);
+//    Log::Info("unproject %d x %d", main_window_attributes_.viewport.x, main_window_attributes_.viewport.y);
 
     glm::vec3 point = glm::unProject(coordinates, modelview, Projection(), viewport);
 
diff --git a/Scene.cpp b/Scene.cpp
index a17b17c..1ba6b7d 100644
--- a/Scene.cpp
+++ b/Scene.cpp
@@ -17,6 +17,8 @@
 #include <algorithm>
 
 
+Group *Scene::limbo = new Group;
+
 glm::mat4 transform(glm::vec3 translation, glm::vec3 rotation, glm::vec3 scale)
 {
     glm::mat4 View = glm::translate(glm::identity<glm::mat4>(), translation);
@@ -179,13 +181,13 @@ void Primitive::deleteGLBuffers_()
 // Group
 Group::~Group()
 {
-    for(auto it = children_.begin(); it != children_.end(); ) {
+    for(NodeSet::iterator it = children_.begin(); it != children_.end(); ) {
         // this group is not parent of that node anymore
         (*it)->parents_.remove(this);
         // if this group was the only remaining parent
         if ( (*it)->parents_.size() < 1 )
-            // delete the child
-            delete (*it);
+            // put the child in limbo
+            Scene::limbo->addChild( *it );
         // erase this iterator from the list
         it = children_.erase(it);
     }
@@ -197,6 +199,7 @@ void Group::addChild(Node *child)
     child->parents_.push_back(this);
 }
 
+
 void Group::detatchChild(Node *child)
 {
     NodeSet::iterator it = std::find_if(children_.begin(), children_.end(), hasId(child->id()));
@@ -375,14 +378,31 @@ void Animation::accept(Visitor& v)
     v.visit(*this);
 }
 
-Scene::Scene()
+Scene::Scene(): root_(nullptr)
 {
     root_ = new Group;
 }
 
 Scene::~Scene()
 {
-    delete root_;
+    deleteNode(root_);
+}
+
+
+void Scene::deleteNode(Node *node)
+{
+    for(auto it = node->parents_.begin(); it != node->parents_.end();){
+        (*it)->detatchChild(node);
+    }    
+
+    limbo->addChild(node);
+}
+
+void Scene::update(float dt)
+{
+    root_->update( dt );
+
+    // remove nodes from limbo
 }
 
 void Scene::accept(Visitor& v)
diff --git a/Scene.h b/Scene.h
index 0bcfb9a..2d402ac 100644
--- a/Scene.h
+++ b/Scene.h
@@ -45,12 +45,13 @@ class Node {
     int       id_;
     bool      initialized_;
 
+
 public:
     Node ();
-    virtual ~Node ();
 
     // unique identifyer generated at instanciation
     inline int id () const { return id_; }
+//    void detatch();
 
     // must initialize the node before draw
     virtual void init() { initialized_ = true; }
@@ -71,6 +72,9 @@ public:
 
     glm::mat4 transform_;
     glm::vec3 scale_, rotation_, translation_;
+
+protected:
+    virtual ~Node ();
 };
 
 
@@ -91,9 +95,10 @@ public:
  */
 class Primitive : public Node {
 
+
 public:
     Primitive(Shader *s = nullptr) : Node(), shader_(s), vao_(0), drawMode_(0), drawCount_(0) {}
-    virtual ~Primitive();
+
 
     virtual void init () override;
     virtual void accept (Visitor& v) override;
@@ -110,6 +115,7 @@ protected:
     std::vector<glm::vec2>     texCoords_;
     std::vector<uint>  indices_;
     virtual void deleteGLBuffers_();
+    virtual ~Primitive();
 };
 
 //
@@ -151,9 +157,9 @@ private:
  */
 class Group : public Node {
 
+
 public:
     Group() : Node() {}
-    virtual ~Group();
 
     virtual void update (float dt) override;
     virtual void accept (Visitor& v) override;
@@ -168,6 +174,8 @@ public:
 
 protected:
     NodeSet children_;
+    // destructor
+    virtual ~Group();
 };
 
 /**
@@ -239,12 +247,18 @@ public:
 
     void accept (Visitor& v);
 
+    void update(float dt);
+
+//    void addNode(Node *);
+
+
     Group *root() { return root_; }
 
     // Node *find(int id);
     // void remove(Node *n);
     //
-
+    static void deleteNode(Node *node);
+    static Group *limbo;
 };
 
 
diff --git a/Session.cpp b/Session.cpp
index b652f01..78a5cb8 100644
--- a/Session.cpp
+++ b/Session.cpp
@@ -9,13 +9,14 @@ Session::Session()
 }
 Session::~Session()
 {
-    // TODO delete all sources
+    // delete all sources
     for(auto it = sources_.begin(); it != sources_.end(); ) {
         // delete source
         delete (*it);
         // erase this iterator from the list
         it = sources_.erase(it);
     }
+
 }
 
 // update all sources
@@ -54,6 +55,7 @@ SourceList::iterator Session::deleteSource(Source *s)
 
         // remove the source and delete it
         sources_.remove(s);
+
         delete s;
 
         // return
diff --git a/Source.cpp b/Source.cpp
index a8aec3e..b8bd1fb 100644
--- a/Source.cpp
+++ b/Source.cpp
@@ -45,14 +45,17 @@ Source::Source(const std::string &name) : name_(name), initialized_(false)
 Source::~Source()
 {
     // delete render objects
-    delete rendershader_;
     if (renderbuffer_)
         delete renderbuffer_;
 
-    // delete groups and their children
-    delete groups_[View::RENDERING];
-    delete groups_[View::MIXING];
-    delete groups_[View::GEOMETRY];
+    // all groups and their children are deleted in the scene
+    // this includes rendersurface_ , overlay_, blendingshader_ and rendershader_
+//    delete groups_[View::RENDERING];
+//    delete groups_[View::MIXING];
+//    delete groups_[View::GEOMETRY];
+    Scene::deleteNode(groups_[View::RENDERING]);
+    Scene::deleteNode(groups_[View::MIXING]);
+    Scene::deleteNode(groups_[View::GEOMETRY]);
     groups_.clear();
 
 }
diff --git a/UserInterfaceManager.cpp b/UserInterfaceManager.cpp
index 0e8b298..37e3236 100644
--- a/UserInterfaceManager.cpp
+++ b/UserInterfaceManager.cpp
@@ -1,7 +1,6 @@
 #include <iostream>
 #include <cstring>
 #include <sstream>
-#include <thread>
 
 // ImGui
 #include "imgui.h"
@@ -32,7 +31,6 @@
 #include "defines.h"
 #include "Log.h"
 #include "SystemToolkit.h"
-#include "TextEditor.h"
 #include "UserInterfaceManager.h"
 #include "RenderingManager.h"
 #include "Resource.h"
@@ -48,34 +46,36 @@
 #include "ImageShader.h"
 #include "ImageProcessingShader.h"
 
-static std::thread loadThread;
-static bool loadThreadDone = false;
+#include "TextEditor.h"
 static TextEditor editor;
 
+
+static std::thread FileDialogThread_;
+static bool FileDialogFinished_ = false;
+static std::string FileDialogFilename_ = "";
+
+
 void ShowAboutGStreamer(bool* p_open);
 void ShowAboutOpengl(bool* p_open);
 void ShowAbout(bool* p_open);
 
-static void NativeOpenFile(std::string ext) 
+static void FileDialogOpen(std::string path)
 { 
-
      char const * lTheOpenFileName;
-     char const * lFilterPatterns[2] = { "*.txt", "*.text" };
+     char const * lFilterPatterns[2] = { "*.vmx" };
 
-     lTheOpenFileName = tinyfd_openFileDialog( "Open a text file", "", 2, lFilterPatterns, nullptr, 0);
+     lTheOpenFileName = tinyfd_openFileDialog( "Open a session file", path.c_str(), 1, lFilterPatterns, nullptr, 0);
 
      if (!lTheOpenFileName)
      {
-        tinyfd_messageBox(APP_TITLE, "Open file name is NULL.             ", "ok", "warning", 1);
+        FileDialogFilename_ = "";
      }
      else
      {
-        char buf[1024];
-        sprintf( buf, "he selected file is :\n %s", lTheOpenFileName );
-        tinyfd_messageBox(APP_TITLE, buf, "ok", "info", 1);
+        FileDialogFilename_ = std::string( lTheOpenFileName );
      }
 
-     loadThreadDone = true;
+     FileDialogFinished_ = true;
 }
 
 
@@ -286,12 +286,16 @@ void UserInterface::handleMouse()
 
 
         }
-
-
+        if ( ImGui::IsMouseDoubleClicked(ImGuiMouseButton_Left) )
+        {
+            // display the info on source in left pannel
+            navigator.showPannelSource( Mixer::manager().indexCurrentSource() );
+        }
 
     }
 }
 
+
 void UserInterface::NewFrame()
 {
     // Start the Dear ImGui frame
@@ -306,6 +310,11 @@ void UserInterface::NewFrame()
     // navigator bar first
     navigator.Render();
 
+    // handle FileDialog
+    if (FileDialogFinished_) {
+        FileDialogFinished_ = false;
+        Mixer::manager().open(FileDialogFilename_);
+    }
 }
 
 void UserInterface::Render()
@@ -370,10 +379,13 @@ void UserInterface::showMenuFile()
 {
     // TODO : New
     if (ImGui::MenuItem( ICON_FA_FILE "  New", "Ctrl+W")) {
-
+        Mixer::manager().newSession();
+        navigator.hidePannel();
     }
     if (ImGui::MenuItem( ICON_FA_FILE_UPLOAD "  Open", "Ctrl+O")) {
-//                UserInterface::manager().OpenFileMedia();
+        // launch file dialog to open a session file
+        FileDialogThread_ = std::thread(FileDialogOpen, "./");
+        navigator.hidePannel();
     }
     if (ImGui::MenuItem( ICON_FA_FILE_DOWNLOAD "  Save", "Ctrl+S")) {
 //                UserInterface::manager().OpenFileMedia();
@@ -406,6 +418,7 @@ void ToolBox::Render()
     // first run
     ImGui::SetNextWindowPos(ImVec2(40, 40), ImGuiCond_FirstUseEver);
     ImGui::SetNextWindowSize(ImVec2(400, 300), ImGuiCond_FirstUseEver);
+    ImGui::SetNextWindowSizeConstraints(ImVec2(350, 300), ImVec2(FLT_MAX, FLT_MAX));
     if ( !ImGui::Begin(IMGUI_TITLE_TOOLBOX, &Settings::application.toolbox,  ImGuiWindowFlags_MenuBar) )
     {
         ImGui::End();
@@ -429,18 +442,6 @@ void ToolBox::Render()
         ImGui::EndMenuBar();
     }
 
-    // TEMPLATE CODE FOR FILE BROWSER
-//    if( ImGui::Button( ICON_FA_FOLDER_OPEN " Open File" ) && !loadThread.joinable())
-//    {
-//        loadThreadDone = false;
-//        loadThread = std::thread(NativeOpenFile, "hello");
-//    }
-
-//    if( loadThreadDone && loadThread.joinable() ) {
-//        loadThread.join();
-//        // TODO : deal with filename
-//    }
-
     ImGui::End(); // "v-mix"
 
 
@@ -484,17 +485,26 @@ void ToolBox::Render()
     }
 }
 
+
 void UserInterface::RenderPreview()
 {
+    struct CustomConstraints // Helper functions for aspect-ratio constraints
+    {
+        static void AspectRatio(ImGuiSizeCallbackData* data) { float *ar = (float*) data->UserData; data->DesiredSize.x = (*ar * data->CurrentSize.y) - 70.f; }
+
+    };
+
     FrameBuffer *output = Mixer::manager().session()->frame();
     if (output)
     {
+        float ar = output->aspectRatio();
         ImGui::SetNextWindowPos(ImVec2(850, 450), ImGuiCond_FirstUseEver);
         ImGui::SetNextWindowSize(ImVec2(380, 260), ImGuiCond_FirstUseEver);
+        ImGui::SetNextWindowSizeConstraints(ImVec2(300, 200), ImVec2(FLT_MAX, FLT_MAX), CustomConstraints::AspectRatio, &ar);
         ImGui::Begin(ICON_FA_LAPTOP " Preview", &Settings::application.preview,  ImGuiWindowFlags_NoScrollbar);
         float width = ImGui::GetContentRegionAvail().x;
 
-        ImVec2 imagesize ( width, width / output->aspectRatio());
+        ImVec2 imagesize ( width, width / ar);
         ImGui::Image((void*)(intptr_t)output->texture(), imagesize, ImVec2(0.f, 0.f), ImVec2(1.f, -1.f));
 
         ImGui::End();
@@ -517,6 +527,7 @@ void UserInterface::RenderMediaPlayer()
 
     ImGui::SetNextWindowPos(ImVec2(200, 200), ImGuiCond_FirstUseEver);
     ImGui::SetNextWindowSize(ImVec2(400, 400), ImGuiCond_FirstUseEver);
+    ImGui::SetNextWindowSizeConstraints(ImVec2(350, 300), ImVec2(FLT_MAX, FLT_MAX));
     if ( !ImGui::Begin(IMGUI_TITLE_MEDIAPLAYER, &Settings::application.media_player,  ImGuiWindowFlags_NoScrollbar) || !show)
     {
         ImGui::End();
@@ -748,6 +759,17 @@ void Navigator::clearSelection()
         selected_button[i] = false;
 }
 
+void Navigator::showPannelSource(int index)
+{
+    selected_source_index = index;
+}
+
+void Navigator::hidePannel()
+{
+    clearSelection();
+    selected_source_index = -1;
+}
+
 void Navigator::Render()
 {
     ImGuiIO& io = ImGui::GetIO();
@@ -845,7 +867,12 @@ void Navigator::Render()
     // window to create a source
     else if (selected_button[NAV_NEW])
     {
-        RenderNewPannel();
+        // if a source is selected in the meantime, revert to selected source pannel
+        if (Mixer::manager().indexCurrentSource() > -1 )
+            selected_button[NAV_NEW] = false;
+        else
+            // show new source pannel
+            RenderNewPannel();
     }
     // window to configure a selected source
     else if (selected_source_index > -1)
@@ -853,7 +880,11 @@ void Navigator::Render()
         // manipulate current source, and activate corresponding button
         clearSelection();
         selected_button[Mixer::manager().indexCurrentSource()] = true;
-        RenderSourcePannel(Mixer::manager().currentSource());
+        Source *s = Mixer::manager().currentSource();
+        if (s)
+            RenderSourcePannel(s);
+        else
+            selected_source_index = -1;
     }  
 
     ImGui::PopStyleColor(2);
@@ -861,41 +892,43 @@ void Navigator::Render()
 
 }
 
-
+// Source pannel : *s was checked before
 void Navigator::RenderSourcePannel(Source *s)
 {
-    if (s)
+    // Next window is a side pannel
+    ImGui::SetNextWindowPos( ImVec2(width, 0), ImGuiCond_Always );
+    ImGui::SetNextWindowSize( ImVec2( 5.f * width, height), ImGuiCond_Always );
+    ImGui::SetNextWindowBgAlpha(0.85f); // Transparent background
+    if (ImGui::Begin("##navigatorSource", NULL, ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoDecoration |  ImGuiWindowFlags_NoSavedSettings | ImGuiWindowFlags_NoFocusOnAppearing | ImGuiWindowFlags_NoNav))
     {
-        // Next window is a side pannel
-        ImGui::SetNextWindowPos( ImVec2(width, 0), ImGuiCond_Always );
-        ImGui::SetNextWindowSize( ImVec2( 5.f * width, height), ImGuiCond_Always );
-        ImGui::SetNextWindowBgAlpha(0.85f); // Transparent background
-        if (ImGui::Begin("##navigatorNewSource", NULL, ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoDecoration |  ImGuiWindowFlags_NoSavedSettings | ImGuiWindowFlags_NoFocusOnAppearing | ImGuiWindowFlags_NoNav))
-        {
-            // TITLE
-            ImGuiToolkit::PushFont(ImGuiToolkit::FONT_LARGE);
-            ImGui::Text("Source");
-            ImGui::PopFont();
-
-            static char buf5[128];
-            sprintf ( buf5, "%s", s->name().c_str() );
-            ImGui::SetNextItemWidth(IMGUI_RIGHT_ALIGN);
-            if (ImGui::InputText("Name", buf5, 64, ImGuiInputTextFlags_CharsNoBlank)){
-                Mixer::manager().renameSource(s, buf5);
-            }
-            // blending pannel
-            static ImGuiVisitor v;
-            s->blendingShader()->accept(v);
-            // preview
-            float width = ImGui::GetContentRegionAvail().x IMGUI_RIGHT_ALIGN;
-            ImVec2 imagesize ( width, width / s->frame()->aspectRatio());
-            ImGui::Image((void*)(uintptr_t) s->frame()->texture(), imagesize);
-            // image processing pannel
-            s->processingShader()->accept(v);
+        // TITLE
+        ImGuiToolkit::PushFont(ImGuiToolkit::FONT_LARGE);
+        ImGui::Text("Source");
+        ImGui::PopFont();
 
+        static char buf5[128];
+        sprintf ( buf5, "%s", s->name().c_str() );
+        ImGui::SetNextItemWidth(IMGUI_RIGHT_ALIGN);
+        if (ImGui::InputText("Name", buf5, 64, ImGuiInputTextFlags_CharsNoBlank)){
+            Mixer::manager().renameSource(s, buf5);
+        }
+        // blending pannel
+        static ImGuiVisitor v;
+        s->blendingShader()->accept(v);
+        // preview
+        float preview_width = ImGui::GetContentRegionAvail().x IMGUI_RIGHT_ALIGN;
+        ImVec2 imagesize ( preview_width, preview_width / s->frame()->aspectRatio());
+        ImGui::Image((void*)(uintptr_t) s->frame()->texture(), imagesize);
+        // image processing pannel
+        s->processingShader()->accept(v);
+        // delete button
+        ImGui::Text(" ");
+        if ( ImGui::Button("Delete", ImVec2(ImGui::GetContentRegionAvail().x, 0)) ) {
+
+            Mixer::manager().deleteSource(s);
         }
-        ImGui::End();
     }
+    ImGui::End();
 }
 
 void Navigator::RenderNewPannel()
@@ -916,9 +949,9 @@ void Navigator::RenderNewPannel()
         ImGui::Combo("Type", &new_source_type, "Media\0Render\0Clone\0");
         if (new_source_type == 0) {
 
-            static char filename[128];
+            static char filename[128] = "file:///home/bhbn/Videos/iss.mov";
             if (ImGuiToolkit::ButtonIcon(2, 5)) {
-
+                // browse file
             }
             ImGui::SameLine(0, 10);
             ImGui::SetNextItemWidth(IMGUI_RIGHT_ALIGN);
@@ -927,6 +960,11 @@ void Navigator::RenderNewPannel()
             // Description
             ImGuiToolkit::HelpMarker("A Media source displays an image or a video file.");
 
+            ImGui::Text(" ");
+            if ( ImGui::Button("Create !", ImVec2(5.f * width - padding_width, 0)) ) {
+                Mixer::manager().createSourceMedia(filename);
+                selected_button[NAV_NEW] = false;
+            }
         }
         else if (new_source_type == 1){
 
@@ -937,11 +975,6 @@ void Navigator::RenderNewPannel()
             ImGuiToolkit::HelpMarker("A Clone source duplicates the content of another source.");
         }
 
-        if ( ImGui::Button("Create !", ImVec2(5.f * width - padding_width, 0)) ) {
-
-            selected_button[NAV_NEW] = false;
-        }
-
     }
     ImGui::End();
 }
@@ -952,14 +985,17 @@ void Navigator::RenderMainPannel()
     ImGui::SetNextWindowPos( ImVec2(width, 0), ImGuiCond_Always );
     ImGui::SetNextWindowSize( ImVec2( 5.f * width, height), ImGuiCond_Always );
     ImGui::SetNextWindowBgAlpha(0.85f); // Transparent background
-    if (ImGui::Begin("##navigatorNewSource", NULL, ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoDecoration |  ImGuiWindowFlags_NoSavedSettings | ImGuiWindowFlags_NoFocusOnAppearing | ImGuiWindowFlags_NoNav))
+    if (ImGui::Begin("##navigatorMain", NULL, ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoDecoration |  ImGuiWindowFlags_NoSavedSettings | ImGuiWindowFlags_NoFocusOnAppearing | ImGuiWindowFlags_NoNav))
     {
         // TITLE
         ImGuiToolkit::PushFont(ImGuiToolkit::FONT_LARGE);
         ImGui::Text(APP_NAME);
         ImGui::PopFont();
 
-        if (ImGui::BeginMenu("Session"))
+        ImGui::Text("Session");
+        ImGui::SameLine();
+        ImGui::SetCursorPosX( 5.f * width IMGUI_RIGHT_ALIGN);
+        if (ImGui::BeginMenu("File"))
         {
             UserInterface::manager().showMenuFile();
             ImGui::EndMenu();
diff --git a/UserInterfaceManager.h b/UserInterfaceManager.h
index 3ae82aa..f64fd17 100644
--- a/UserInterfaceManager.h
+++ b/UserInterfaceManager.h
@@ -1,6 +1,7 @@
 #ifndef __UI_MANAGER_H_
 #define __UI_MANAGER_H_
 
+#include <thread>
 #include <string>
 #include <list>
 using namespace std;
@@ -15,19 +16,19 @@ class Source;
 
 class Navigator
 {
+    // geometry left bar
+    float width;
+    float height;
+    float sourcelist_height;
+    float padding_width;
+
     // top items : group of buttons openning a pannel
     int selected_source_index;
     bool selected_button[NAV_COUNT];
     void clearSelection();
     void toggle(int index);
 
-    // bottom items : individual buttons
-
-    float width;
-    float height;
-    float sourcelist_height;
-    float padding_width;
-
+    // side pannels
     void RenderSourcePannel(Source *s);
     void RenderNewPannel();
     void RenderMainPannel();
@@ -35,6 +36,8 @@ class Navigator
 public:
     Navigator();
 
+    void hidePannel();
+    void showPannelSource(int index);
     void Render();
 };
 
@@ -51,6 +54,8 @@ public:
     void Render();
 };
 
+// TODO: class ShaderEditor
+
 class UserInterface
 {
     friend class Navigator;
@@ -68,6 +73,16 @@ class UserInterface
     void handleMouse();
     void showMenuFile();
 
+//    typedef enum {
+//        FILE_DIALOG_INACTIVE = 0,
+//        FILE_DIALOG_ACTIVE,
+//        FILE_DIALOG_FINISHED
+//    } FileDialogStatus;
+//    FileDialogStatus filestatus_;
+//    std::string filename_;
+//    std::thread filethread_;
+//    void startOpenFileDialog();
+
     // Private Constructor
     UserInterface();
     UserInterface(UserInterface const& copy);            // Not Implemented
diff --git a/View.cpp b/View.cpp
index 8c4d6c1..75fb97e 100644
--- a/View.cpp
+++ b/View.cpp
@@ -39,7 +39,7 @@ void View::saveSettings()
 void View::update(float dt)
 {
     // recursive update from root of scene
-    scene.root()->update( dt );
+    scene.update( dt );
 }
 
 MixingView::MixingView() : View(MIXING)
diff --git a/main.cpp b/main.cpp
index 60231d8..042df03 100644
--- a/main.cpp
+++ b/main.cpp
@@ -106,11 +106,11 @@ int main(int, char**)
     Rendering::manager().PushFrontDrawCallback(drawScene);
 
     // init elements to the scene
-    if ( !Mixer::manager().open("./testsession.vmx") )
-    {
-        Mixer::manager().createSourceMedia("file:///home/bhbn/Videos/iss.mov");
-        Mixer::manager().createSourceMedia("file:///home/bhbn/Videos/fish.mp4");
-    }
+//    if ( !Mixer::manager().open("./testsession.vmx") )
+//    {
+//        Mixer::manager().createSourceMedia("file:///home/bhbn/Videos/iss.mov");
+//        Mixer::manager().createSourceMedia("file:///home/bhbn/Videos/fish.mp4");
+//    }
 
 //    Animation A;
 //    A.translation_ = glm::vec3(0.f, 0.f, 3.f);
@@ -135,7 +135,7 @@ int main(int, char**)
         Rendering::manager().Draw();
     }
 
-    Mixer::manager().save("./testsession.vmx");
+//    Mixer::manager().save("./testsession.vmx");
 
     UserInterface::manager().Terminate();
     Rendering::manager().Terminate();