No guarantees using this method. Given there is a huge variation in the skill of car creators & produced quality, there are a lot of variables at play. Redo the edits with fresh files & try the import again (CW may have messed up the import). Also make sure OpenIV isn't open while you do the import.
What car was it you were trying to edit (link to the download) & what extras are you trying to remove/disable?
Also, what kind of crash was it? Did it crash on startup or in game, & was there any error message displayed?