Well, here’s an interesting proof of concept that decided to present itself: http://www.renderosity.com/mod/bcs/la-robe-de-gala/72815
Casual shirt and a bra/halter top thing presented in the main promo image. The actual product is a dress. Simple material zones more or less created 3 different things to use ranging within the covered and skimpy spectrum. Granted this is V4 rather than Genesis but the actual example is still perfectly sound.
Its GOT to be the wrong main promo image. Everything is about a dress CR2 and mats - only the main promo image is a top & pants. Now if Rendo offered a money-back guarantee I’d snap it up in a sec just in case.
But no - methinks mistak-o.
EDIT: ... or the tops are dress mats and the pants aren’t included. Its simply not possible geometrically speaking for a dress to become pants, much like I will never be a millionaire.