If there is nothing intersecting the body have you tried just using the clothing OBJ file? A quick work around for intersecting parts is to set them into the constrained group. For a figure hugging body suit like the one you mention try assigning everything to the constrained group. When its that tight will there be any difference to the conforming version? Try it and see.

As to why you were left with nothing after deleting the figure, you either did not spawn the prop or deleted it or .... ???? but for that I think I'd need to be watching over your shoulder as you did it :)