Going back to defaults?

[Othesus]

There are some variants for the bag and maintained windows if you haven't tried those.

To go back to the default just delete these files in your ProfitUI folder.
eq2ui_inventory_inventory.xml
eq2ui_inventory_bag.xml
eq2ui_mainhud_maintained.xml

If you use the auto-updater then you'll need to go into the ignored files window and double click those files to make them red so the auto-updater won't download them again.