Monodevelop says it's building then doesn't launch the game.

I am using Windows 7. I pretty much have just been editing my scripts, saving, then manually starting the game in the editor... for about a year or so since I've been using unity. It's getting annoying because I often forget to save and everything else I use, you push F5... and it works. I set the Unity > editor location option manually in Mono, but that changed nothing. I get no errors unless Unity isn't already open, then if I run from Mono I get the "Unity Editor not found" pop up.

I've tried lots of things but can't find anything about it. I keep getting hits for "Monodevelop won't launch" or similar but that's not my problem. I just want to hit F5, have it save my changes, then launch the game for testing/debugging. I've suffered long enough without the one push convenience, let alone without any debugging save for using print() and public variables in the inspector... :P