Deactivating and reactivating Ultimate Post Type Manager 1.6.8 may cause custom field data loss if the data was stored using multiple checkboxes for a field.
1. Create a custom post type "foo" with a custom field attached who has values "A", "B", and "C" available as checkboxes.
2. Create a new "foo", check off "A", "B", "C"
3. Save - confirm you see "A", "B", "C" checked off.
4. Go to Plugins and deactivate UPTM
5. Enable UPTM
6. Edit the "foo" your created - the fields are no longer checked off
THERE IS NO WORKAROUND - THIS IS A CRITICAL BUG THAT WILL CAUSE YOU TO LOSE DATA WITH NO RECOVERY EXCEPT FROM A DATABASE BACKUP IF YOU HAVE ONE.
I went into the database and examined the wp_postmeta before deactivate/reactivate and after. Here's before:
DO NOT DEACTIVATE/REACTIVATE THIS PLUGIN UNTIL THIS HAS BEEN CONFIRMED FIXED BY XYDAC.
XYDAC - I'll try to help with this but first I have to try to recover as much data as possible from a backup file.