One day I was working on a project when my computer blue screened. I restarted my PC and all of a sudden my Radiant wont start. I removed everything on regedit and even reinstalled it to no luck. I even tried to check for updates.

I think the first think that you should do is to check your MOD TOOLS integrity via Steam (search on Google and you will find how), if this doesn't work, try creating a new map, but, overryding it's .map by the other map .map. Hope it helps