You are an experienced programmer and have a problem with the engine, shaders, or advanced effects? Here you'll get answers. No questions about C++ programming or topics which are answered in the tutorials!
I get this warning message "Could not release opengl dc" when I quit my program and a similar one also using directx. Only the software renderer seems to work well.
This is just a small bug in the engine, which I did not fix yet. You simply may ignore it, it does not cause any problems. If you don't like the text printed out, you can absorb it with the new event receiver in 0.4.2.