TypeLoadExpection, cannot use types from libraries from my project
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I'm making some kind of game engine. I've got problem with TypeLoadExpection.
This is how my solution explorer looks:

http://screenshooter.net/data/uploads/rc/sg/cohk.jpg (I'm posting it as link because I don't have enough rep.)

If I use any of types from PolyEngine in PolyEngineRuntime, I'm getting TypeLoadExpection!
I have no idea why it's happening. I can post code if it helps to solve the problem, but I don't think the code will be useful.