I see this thread was moved, however I originally posted in the general WinXP subforum because I wasn't sure that my issue had anything to do with either of the tools I had used in creating the initial installation. I mentioned them because I thought they may be relevant to the solution.
First, nLite is not for Commercial Use (you said "office").
I see no mention of that on nliteos.com. It only says Freeware, with no other stipulations specified. If that is not the case, then that was my mistake...
Second, BSOD 7b is technically "0x0000007b" and further info is given, which you failed to provide.
Yes, it was 0x0000007b, not having the exact code next to me I just left out the obligatory 0x00's. There was however no other message or description aside from the generic text on every BSOD screen. There was no name or description. I did not make a note of the following codes (if there were any) because it was not my intention at the time to post here for assistance. And now that I have, I am not currently at the office so I can not confirm any further codes at this very moment. If needed, I will do so later.
Third, that's "basically" Inaccessible Boot Device.
I've had a look at that page, and another linked at the bottom that sounds even more specific to my case (KB314082: You receive a Stop 0x0000007B error after you move the Windows XP system disk to another computer), however that one suggests the problem should not occur when the secondary computer has all of the same hardware. Other things mentioned in KB324103 (viruses, driver issues, etc) sound like they should also result in the cloned drive causing a BSOD when it's installed in the original "source" PC, however that does not happen. All three clones boot into Windows on the original PC. But all of the clones have the same BSOD when installed in the other three PCs.
Compare storage controller BIOS settings.
BIOS settings on each PC should all be the same defaults except for changing the SATA ports to AHCI, rather than their default which if I remember correctly was RAID. I will double-check my settings and report back. I suppose I could also try using the RAID and IDE settings instead of AHCI.