Well nice to see that I've been welcomed back into the fold! Funnily enough someone emailed me for advice about which model to buy and I looked on this forum for a post I remember writing about the difference between air and standard suspension and the different merits of each engine - and of course I'd removed it. Doh!
We never really got to the bottom of the reason for the original battery failure. When it went in for the CD changer replacement I got a Workshop Running Gear Fault upon collection (typical result of a low battery charge) which (as the technician advised) disappeared after the alternator had juiced the battery for a bit. Then I had the tow bar fitted not long after and the same Workshop Running Gear Fault appeared. After that the battery was completely dead a few times when I went to the car in the morning (sometimes fine for weeks, sometimes dead overnight!) and got fed-up with using a trickle charger so it went in for VW to check. I had to pay for the labour (battery is handily located beneath the drivers (electric) seat but the battery test proved it was completely goosed / cells buckled so they put a new one in (despite arguing, perhaps reasonably) that the low usage the car has might be a contributing factor. Been fine ever since...
What works are done during the 90D7 recall are entirely dependent upon the model and its history. Mine needed the following: 01, 04, 10, 15, 16, 21 and 22 which equated to a new wiring loom for the starter motor (nightmare engine out job apparently), a new water pump, a hard wired connection beneath the drivers seat rather than the previous sliding contact and software upgrades.