PEX Issues (Ranks)

I WOULD LIKE:
-2 Ladders *Keep in mind Default Rank is lowest or (highest in number) in ranking
One Donator Ladder For ranks (Brute,Elite,Beast and Barbarian) In Least To Greatest Rank Order
And One Staff Ladder For ranks (Helper, Moderator, Admin, Owner) Continuing Least To Greatest Rank Order
DONATER
I would like Brute to inherit Default
Elite inherits Brute and Default
Beast inherits Elite,Brute and Default
Barbarian inherits Beast, Elite, Brute, and Default
STAFF:
I would like Helper to inherit Default
Moderator inherits Helper and Default
Admin inherits Moderator, Helper, and Default
Owner is by himself.

I want it so through buycraft (Where Command is used to rank players to the bought donator rank)
A command such as /pex user <user> group set <group> Is used or something similar so I can have that preset so it will be automatically done through Buycraft.

ISSUE:
Currently Default rank works fine, commands and etc..
However as soon as I use '/pex user <user> group set <group' Whether from ingame or console the rank other than default will mess up, prefixes won't work and commands won't work at all. I can then just as easily set them back to default rank and it will all work again.
This issue has been very problematic with one issue resolve turning into a much larger issue.
Please help, thank you.
PERMISSIONS:
http://pastebin.com/HBFhES01