Turned out that my engine wasn't really ready for the game state management implementation. Things quickly started acting strange when I switched, displaying all kinds of odd problems. I realized quickly that this would require some from ground up refactoring of how some core systems work in order to get right...

So I started a fresh project and reimplement each system with better structure and factoring. Shouldn't take me more than another day or two, which I have time for. Still, kind of disheartening. I had hoped to throw in screen handling in a matter of hours :P Instead it ends up taking several days... Guess that's one system I shouldn't have left out from the start, since it digs so deep into how the entire engine work together really. I'll keep that in mind for my next project!