I have double-checked my paths in both config-inc.php and config-int.php, they are correct.
A little more info:
1) if I delete all PhotoPost tables from the new server, and then import a mysqldump of all tables from the old server, when I visit our gallery, I get a blank page (page source is 100% blank)
2) If after #1, I empty the pp_cache table, I see our site header, but NOTHING from photopost (you can see that here: http://www.scrapbookmax.com/gallery/
3) Even with some incorrect paths in the config-inc.php and config-int.php files on our old server, the gallery still works, without styles (Exact same database and files) -- you can see that here: http://220.127.116.11/gallery/
4) I have set the appropriate permissions on the new server in /gallery/
5) Just to reiterate from above, with nothing in the pp_categories table, the gallery on the new server works great. As I bring in a few rows at a time into the category table, the gallery continues to work, and then eventually fails as seein in #2 above. However, if I then import rows starting a few before the problem row, the gallery works again, to a point, then fails in #2.
I'm at a complete loss here -- is there a way to debug this? Any suggestions beyond checking paths? Please help -- i'm pulling my hair out here!