Just googled it. Couldn't find any diagrams but that guitar also has a piezo bridge pickup and a battery box in the rear (for the piezo pre-amp, most likely). I would guess that the standard pots are master volume/tone for the magnetic pickups, the concentric pot is volume (tone?) for the piezo and the mini-toggle is a selector for the magnetic pickups vs. piezo (and maybe both on at the same time.)
Is everything screwed up? If it's just the magnetic pickups then that's easy to fix. If the piezo/pre-amp is messed up then you'll need some help from someone other than me!