Dualboot Lab Imaging

Hello, my school has a computer lab which we have switched from dells to mid-2010 mac mini's a while back. Classes require both OS X and windows xp which we have on the computers. The previous lab manager imaged the computers one by one with either target disk mode or an external hard drive. This process works but is not very efficient as you can imagine. I configured our server and resolved the networking issues that now allow us to use the NetRestore service for the OS X partition. I've also used ARD to push the windows.dmg on to the admin's desktop and can run a unix command to asr the windows partition. This has saved me a bunch of time in comparison but I've run into problems. He is not sure what he did when he set them up, but we CAN use asr or diskutility to make .dmgs of the windows partition and restore it on the lab computers. We reclaimed a mac-mini that was purchased with the lab computers so we can test software on it without interrupting classes but we CANNOT image this computer like we do the lab. The boot camp partition is not displayed in the boot loader. I know this is a long winded question but if anyone had any experience with this or could suggest a better imaging solution (that is still actually supported or better yet is part of OS X) I'd be very grateful.

Long story short:

-used to use disk utility to restore both OS X and windows XP images one computer at a time.

-I now have NetRestore working and use ARD to copy the windows image to the mac desktop and UNIX command ASR to restore

-an identical computer to the lab was never setup and when we use either of these imaging processes it does not work.