Crash after DLC download (Steam PC)

If anyone could help me that’d be great. I D/L SSF4AE on steam when it released and it played perfectly up until today. The only thing I did was D/L the DLC costumes from the Steam store and now the game crashes as soon as it gets to the title screen after the opening movie. As soon as the title screen comes up it pauses for a second than crashes and shows the “Windows is checking for a solution” dialog box and the game closes. I did have some modded costumes and modded music installed (worked great before) but I deleted everything from Steam and re-downloaded the original game and it still crashes at the same spot.
Anyone have any ideas?
Also if this has been answered somewhere before I’m sorry but I did search and couldn’t find the answer that way.

M11x R2
8tg ram
512gb HD
Nvidia graphics card

Ok if I sign out of Games For Windows Live and then hit start (Z) it will load the title screen fine but than if I try to sign in after that it says my “Gamer profile has changed and the game connot continue. Returning to the title screen.” Than if I try to start the game (while now signed in) it crashes at the title screen again. So I’m guessing it’s a Games For Windows poblem of some kind.
Anyone know what I can do to fix this?


Right clic > proprieties > local files > verify integrity

Ok I guess it works perfectly now. The only thing I did was re-install the music mods and than set it up so Games For Windows Live doesn’t sign me in automatically. Than I signed in manually and set it back up so it signs me in automatically again and it seems to work now. No idea how that changed anything but whatever.
Thanks Whinette for the suggestion. Thankfully it seems to work now.