HELP; Cant select bank 8

[1995k2500]

I have a 1995 Chevy pu, and with the stock chip in i can read my aldl information just fine, but when i try to emulate through apu1, i get the error "FAILURE; bin is larger than emmulation ram, perhaps you meant to use bank 8?" I went to view:toolbar and selected to show the emulation bank dropdown, but it's not allowing mne to drop it down. It's like it's an inactive menu. Im 98% positive i'm using al the correct xdf, ads and adx files, they're all the ones it calls for for V5 with my truck. I've justhit this wall and i need a point in the right direction please!