noveethoresen Does this happen every time you exit CAS, or only some of the time? Does it happen with no mods or custom content present, as in, you've removed the entire Mods folder? Even if you'd never play like that in general, it's a useful test.
If you get crashes with no mods or cc, please provide a dxdiag. Click Windows key-R, enter dxdiag in the run box, wait for the scan to finish, click "Save all information," and save the file to your desktop. From there, you can attach it to a reply using the paper clip (Attachment) icon included with the other formatting buttons.