16 page imposition

[jwhittaker]

I have a 16 page booklet that is 5.5x8.5. I want to create a 16pg imposition on 28"(wide) x 20"(height). It looks just like the Perfect Bound Booklet in FPImposer. The only problem is that it will only show 8 pages instead of 16. I have set the pages per record to 16 in the Document tab. I know it will fit on the sheet since I can step and repeat 2 times horizontally the 8 pager. Am I missing something or is the biggest booklet that FPImposer can do is 8 pages?
I want to put this into FusionPro and then to Marcom but I need to show single pages to the client but impose on a 28x20 sheet. Right now, I'm having to get the single pages approved then copy and paste them into a preimposed indesign doc and run the variable. I'm using XmPie until I can figure the imposition problem out. There will be 150K records with over 100 different art versions.