Honestly it's hard for me to say... if it was corrupted then it wouldn't even appear in the World Editor.
I honestly don't think a shortcut can affect this UNLESS you were in the import manager itself.
Have you tried deleting the model (from the import manager) and re-importing it?
It seems that other custom models work for you, so try that.
PS: I strongly recommend not to use 1.31 to make maps, unless you specifically need that patch for certain reasons.