88 Golf Problem with alarm install

I have installed alarm in a my car , it works off the tremor OK. The negative trigger from the interior light is the problem. The car already has an approved immobilzer, the drivers door trigger does not operate the interior light as this is connected to the immobilizer, it wakes it up I think. All other doors including the boot operate the light. I having allready read about blocking diodes elswhere on the site. As the drivers door is still a -ve trigger , I was thinking off using that but , as I wanna get ICE for the boot I wanna protect that aswell. Is there a way of connecting the -ve trigger directly to the interior light.  

<< "The car already has an approved immobilzer, the drivers door trigger does not operate the interior light as this is connected to the immobilizer, it wakes it up I think.">>

Did you DISCONNECT this to hook up to Immobilizer?

Should be:

Dome Light

BROWN / WHITE

(-) AT PIN SWITCH

Unless those European V W's R different

MO

Don't Learn from Others Mistakes

You Might Be the One That Knows.

"Did you DISCONNECT this to hook up to Immobilizer?" No. It was installed when i got it. All wires going to the immobilizer are black. As it is the same pin switch , the wire must be a -ve wire. I am new to all this. But I reckon its a earth wire, that when the spring pulls away,on door opening, earths the connection, closing the circuit, probably. The haynes manual dosnt help much, for 1 thing I have a 5 door and the circuit diagram is not given. If anyone has installed such a immobilzer, where would the original wire have been cut? What would connecting the rear door switch to the front door switch do? Is there any way of triggering the alarm on any door opening? Without using loads of blocking diodes! https://www.the12volt.com/diodes/diodes.asp