Hi there, skinjob I find myself in exactly the same position as you I also have been driving for almost 20 years and the wife got me a CBT for xmas which I took and passed in early jan, I also went out and picked up a YBR125 the next day for experiance before I do the DAS (which is booked as I have just passed the bike theory) in Feb
I too had problems initially when doing the CBT with coordination but after driving the 125 to work and back now for a few weeks I am starting to find it quiet natural with the brakes and gears, not perfect yet by a long way but coming along in leaps and bounds.
The bank Manager (wife) is very supportive of me and is encouraging me to the the DAS so she can get on the back with me, already bought herself a helmet
Good luck with your test and riding!!
Ade