Uploaded zip files are not stored in the server as zip files. They are automatically unzipped, the image files extracted and processed. So, look for the images within the zip files inside your account.
usually when u upload a zip file, you get status report thst goes something like "abcd.jpg extracted" on the page that follows. If you did not get that, it means your zip file did not make it. How big was your zip file? Maybe the connection timed out?