Build version: no player control, terrain, skybox...

Hey! So I've been building a pretty simple game, mostly just terrain, sound, and movie textures, and it had been working fine when I tested builds in previous versions. Now at my latest version (I've mostly added more movie textures and some 3d text...) when I try to build I get a blank grey screen with a few of my assets rendering (planes, particles) but I have no control over my character and nothing else renders.

Everything works perfectly fine in the game mode of the editor though. I have tried retracing my steps and removing components but even if I take all the added things away it still happens. My older .exe builds still work fine though. None of my layers are unchecked, either. ...

Any idea??? Urrghh... Thanks in advance!