Well, I can help with this:
- I tried extracting the Bios from the "5430A18.exe" file using the /writehdrfile and /writeromfile flags, but got errors and it didn't work.
Those flags will only ever work if that EXE (which is a basically a flasher with embedded firmware data) was intended to let you extract the ROM. They won't do anything otherwise, their function is 100% intrinsic to the program contained in that EXE, not extrinsic. That is, they aren't an operation you do on the file, they are on operation that file does on itself.
- I got stuck when it came time to try to flash the Rom file back. Dell has no separate flash utility for Rom/Bin/HDR files; their Bios files are all EXE. I tried a few flashing programs, but they all said my Rom was an invalid file.
As discussed above, this is because they *are* a specific flasher program with embedded firmware data. Like a bundle.
The biggest problem here is that you have no idea if your "DellInc.-A18.rom" won't just brick your computer if you did manage to flash it. Even if you do find some flashing program which says the file is valid that doesn't mean it'll actually work, much less after you start editing it.
Fundamentally, CompuTrace (or LoJack) is intended to *not* let you do this. That is, if it was *easy* to just *disable*, there isn't much point to it as a feature. Are there flaws? Certainly, but unless they really goofed it up on this one model the kind of thing you are doing really shouldn't even work.