Robin Hoods Playground

Using the 360 Blaster NE on my MS28. After booting up and doing 10 second trick, I use dsam and it goes to 01% and then kicks the ORIG.BIN wrong size error. I checked the Backup file and the Sam-cfw.bin is 256kb, but the Sam-ofw.bin is only 1kb. Any ideas? Done it like 50 times. I am using iPrep 101...