i am not really sure what the 3ds plugin has to do with UV snapshot, what file type are you saving the snapshot as ?

A Uv snapshot is just an image file of your objects uv layout so you need to select an image format i.e jpg,tiff,targa ect

You should not need to delete the preferences every time because if deleting the preferences solves the issue Maya would be using the new preference file it created henceforth.