Listing Shirts (colors/sizes) through Seller Central

Does anyone have experience listing shirts with multiple variations on Seller Central? They recently changed what information needs to be required, but it will not let me list a specific color with a few size differences between my shirts. I have no idea what to do, and the case log is more than useful. They used to allow us to upload smaller images on the product images so that each shirt color could be chosen and seen by the customer. What happened to this feature?