Experts, please help - how would you disable a CompuStar Pro? Trying to re-enable it!
 

I recently bought a mint condition 2001 BMW M Roadster and was pleasantly surprised that it came with a top-of-the-line CompuStar Pro alarm remote, one of my favourite systems. To my chagrin though, the alarm was installed by the first owner and the second owner had paid someone to "disable" it. I believe it is a P2W9000 remote start, or similar.

I want to re-enable it, but the previous owner had no idea how it was disabled or where the CompuStar module is. I don't want to pay someone to tear apart the interior looking for the module, so I am hoping to DIY it if possible.

My question is, if you're an alarm installer, how would you go about disabling the alarm? What are the different ways this can be done? Can you just unplug the harness going into the CompuStar module? Is there a fuse somewhere you would pull?

Some more info, in case it provides any hints:
-the car is a manual transmission, with immobilizer
-I already checked to see if the alarm was "soft-disabled" in valet mode by turning the ignition on and off rapidly 7 times but the alarm module seems to be completely unresponsive
-the car's lowbeams are always on (not normal) - I remember CompuStars need to tap into the lowbeams and are used as a signal for remote start status, could this hint at how the alarm was disabled?

I'm hoping to read as much as I can before I open her up - I'm not quite ready to see what's in there (cut wires? stock wiring spliced back together?) and I'm hoping there's an unintrusive way to unplug / disable the alarm that I can easily undo...