I've only got this module and UPSXML installed. Everything is working fine for shipping, I get quotes and such just fine.
However, now when I go into the admin page to add new products, the screen blanks and I get no errors. I see in the access log a 500 error (but nothing in the error log?).
I'm guessing it's something to do with admin/categories.php. I've gone over the install several times, but to no avail.
Anyone have any troubleshooting ideas? I haven't dealt with PHP in so long, I've forgotten more than I knew.