With True Image 2011 i used this code to boot from ISO:
title Acronis TrueImage 2011 map --mem (hd0,0)/boot/iso/AcronisMedia_2011.iso (hd32) map --hook chainloader (hd32) boot lock
Same code with an ISO of True Image 2012 does not work.
Seems that the mapping works, but the chainloader has a problem, because the computer is freezing then.
I tested the ISO by booting it in a VM. I dont have any problem there.