Runtime .exe doesn't play the game

So my game works fine and dandy inside of Blender, and it used to work when I exported as a runtime. For some reason, though, when I export it now, the game will start up, the menu will work fine, but when it goes to the level, nothing works, the character doesn’t respond to the keys and just jitters slowly back and forth. Any help would be greatly appreciated.

…and now it’s doing the same thing inside of Blender. This is becoming a major issue. Please help.

That sounds odd. Do you have any scripts running in your game that might have changed? Check the console.

Definitely not. I don’t know how to write any scripts, so everything is just logic bricks. The weirdest part is that my autosave from a week ago works fine…until I manually save it. Then it acts like the other ones and stops working. But only for the level scenes. The menus and whatnot work fine. I didn’t change anything from the autosave except for some materials and new objects, but when it gets saved, it gets ruined.

Odd indeed. Are you switching Blender version? Could you put up a blend file?