Alright, I've found the issue, which is the that Essentials expects a minimum number of bag slots. To be honest, I'm not sure where that number is stored, but when ever you go below 8 pockets, the Bag no longer works. (This might be because items in the PBS are labeled 8, so it expects 8, but I'm not sure no willing to change them all to 7 to find out.)
However, there is still a way to reduce your pockets. On the script page "PokemonBag", go to line 14 and change it to look like this
Code:
def self.pocket_count
return self.pocket_names.length+1
end
This will stop it from crashing when you go to the Bag Menu. But you are not done.
On script page "UI_Bag", go to line 386 and change it to this:
Code:
newpocket = (newpocket == 1) ? PokemonBag.pocket_count - 1 : newpocket - 1
And then line 404 and change that to this:
Code:
newpocket = (newpocket == PokemonBag.pocket_count-1) ? 1 : newpocket + 1
That fixes all crashes. Functionally, your bag UI will look kinda gross, since it will have an unused slot. I'd recommend editing that to fit your new layout.
Finally, you will have to change every item in the PBS that is above slot 6 to 1 lower (6 was mail, so you have to change Battle Items from 7 to 6, and Key items for 8 to 7). Otherwise you won't be able to reach your Key Items as they are in slot 8 when you only have 7 slots. Changing your PBS does not auto update items already on your character, so you will have to start a new game if you already have key or battle items.
