Didn't you already say you had an issue with the Master Cylinder?
If my knowledge of the mot is correct, the new system will instruct the tester to look for a functional abs light on yours. It takes a lenient tester to turn a blind eye to one that has been piggy backed off of the airbag or oil pressure switch, as the lights generally illuminate together and then go out seperately on a properly functional one.
I had the abs light up on mine, turns out that I had disturbed a sensor when swapping over the suspension. I would get it code read to see what codes it throws up with the abs and then you are pointed in the right direction.
If you were closer, I would lend you a wiper motor to get yourself sorted out, you shouldn't have to pay any more than a tenner for a wiper motor and mechanism from a breaker/classified, and it is a wiper arms off/scuttle off/3 bolt and one cable connector job.
