Runtime error in Demo_Player sample

Hi there!
I'm having a runtime error in the Demo_Player sample, in the init() function.

void init()
{
CEGUI::Window* sheet = CEGUI::WindowManager::getSingleton().loadWindowLayout((CEGUI::utf8*)"SimpleDemo.layout");
CEGUI::System::getSingleton().setGUISheet(sheet);

EVENT("rgb_button",DemoApp::OnRGB); EVENT("yuv_button",DemoApp::OnYUV); EVENT("grey_button",DemoApp::OnGrey);
EVENT("shaders_button",DemoApp::OnShaders); EVENT("Play/Pause",DemoApp::OnPlayPause);
EVENT_EX("seeker",DemoApp::OnSeekStart,CEGUI::Scrollbar::EventThumbTrackStarted);
EVENT_EX("seeker",DemoApp::OnSeekEnd,CEGUI::Scrollbar::EventThumbTrackEnded);

createQuad("video_quad","video_material",-0.5,1,1,-0.94);

TheoraVideoManager* mgr=TheoraVideoManager::getSingletonPtr();

mgr->setInputName(VIDEO_FILE); <------ HERE, THE ERROR

mgr->createDefinedTexture("video_material");
}


It's strange, because the error raises in an assignment statement (string = string).
The error says:
Unhandled exception at 0x784860f7 in Demo_Player.exe: 0xC0000005: Access violation reading location 0x00000058.

I'm using VS2008, and the lastest svn revision of the plugin.
Any idea?
Thanks in advance,
che1404.

Hi again.
The problem is that the manager is null, and I was trying to access a null object.
But this is a bit wired, because the TheoraPlugin dll is loaded successfuly during the startup, and the constructor is called normally. Any thoughts?

Finally, I had to do this before using TheoraVideoManager:

...
createQuad("video_quad","video_material",-0.5,1,1,-0.94);

// Create our new External Textue Source PlugIn
TheoraVideoManager* theoraVideoPlugin = new TheoraVideoManager();

// Register with Manger
ExternalTextureSourceManager::getSingleton().setExternalTextureSource("ogg_video",theoraVideoPlugin);
Root::getSingleton().addFrameListener(theoraVideoPlugin);

TheoraVideoManager* mgr=TheoraVideoManager::getSingletonPtr();

Ogre::String test = mgr->getInputName();
...


Thanks!