Im still having problems with the setup for this. When I drop the files that will be imposed to 12x18 they impose correctly, but when I drop in the files for 8.5x11 they are setting up as multiple up instead of just 1 up on 8.5x11.
So far so good. Can you send the job file that's the wrong size via private message?
PS> Click on my name and select Send this user a private message from the top, right sidebar.
This is working as expected in my system. I've enclosed the imposition template. Please send your template as I would like to see if there's something different vs the screenshots.