I managed to have the game played, but I wasn't sure what the objective is. Regardless, the animation of the mushroom flying away is pretty funny. It doesnt seem to be a finished game, but I hope you had a fun time :)

The game requires you put the folder in your E:\ drive and call it Blender. It needs a specific path of E:\BLENDER\YOU VS MUSHROMS\Game Archives. 

Cool. Did that.

Now it says my gpu needs OpenGL2.1 support

Bah!

I'm a bit sad that I can't play this game :/