Hi Eddie,
I have a customer trying to download one of my models that he purchased.  I've tried emailing the .zip to him, but I believe he had a problem with that too and now I've uploaded individually extracted .obj and .mtl files and asked him to try downloading them.  I think the issue is file size and download bandwidth limitations on his ISP.  The .zip is 16 MB and the .obj is 81 MB.  I'm not having a problem downloading, extracting or loading the model.  It seems fine for me.
I don't think he will be able to successfully download or receive the model by email. Is there anything you can advise? How can I direct him to the refund process? Thanks for advising.