Re: table 'users_objectpermissions" missing in Tiki15
Hi Mike, best for upgrades to new servers is to transfer the same tiki12.x from old to new server, and proceed with upgrading in the target server over the migrated old db, which Tiki will upgrade for you.
I hope this helps
More information (even if I know, it's a loooong page):
https://doc.tiki.org/Upgrade