I have been uploading both versions of my designs, and smithandsmith uploaded her bunny bag and chickie bag both parts in one upload. This works fine, but the system numbers all the files in one upload the same.

For you to download both parts, in my case the 5x7 and the 4x4 or for smithandsmith's body and wings you must rename the second file. I just add a 2 after the original number. You do this by clicking behind the number and then just typing what you want in there. Hope this helps.