After uploading Max's Pitch Data I get a message saying, "The matching field you chose (Pitch ID) is not mapped and is required for an Update and Insert operation". This is the first error message I have seen from this step.
Sorry you're stuck but there's almost always a pretty easy fix! Don't try to start all over again–not necessary! Don't start undoing stuff and don't uninstall Max's Pitch Package, etc.
There's a 95% chance the same snag/fix is listed & answered in the Help FAQ. Check that first but if you can't find it there, post your problem + a screencap in the proper category below & we'll post a solution back ASAP!