If you set up two or more options as file upload and they are required options, during the upload process, the following error message comes up “The product cannot be added to cart. Check if all the uploading files meet the necessary conditions”.
If you set up one option as file upload and it is required, you can upload the file, but do not have the possibility to delete it again in the cart so that you can upload a different file (the delete X button is missing).
Hello,
You really need to add this to the actual “Bug Tracker” if you want to get any resolution to the the problem… 
OK,
Thanks for the advice