Any chance it's item 7 causing it to go off?
just looking at this list - would a battery in the car that is smaller than what is supposed to be cause this issue/trigger the alarm?
i am getting the same on mine now - started the other day before i took it to the garage - mechanic told me about the battery being different to the size supposed to be in there. i told him about the alarm, but he said the whole time it was with him, it didn't go off. sods law.
also, what is the seat belt issue - my seat belt is slow to retract. could that be causing it?
all these niggly little things. i'll get them all sorted eventually!
on a plus note, i managed to get the tyre pressure sensors done on mine today - so that is one thing fixed anyway. so slowly slowly.