Further to my last posting, the motor has now been fitted and the DZ126 chip fitted and all wired up. Pleasingly, the loco ran the correct way, so there was no need to change CV29. After changing the chip address to 4741 (loco number 44741) I've set the acceleration to 20 (out of 31) and deceleration to 3 (out of 31). This enables a fairly smooth acceleration whilst retaining good control over slowing and stopping. Experience has shown that excessive deceleration values makes fine control on a dead-end layout rather hazardous!
In the photo, the chip is attached to the rear of the motor body by a thin layer of Bluetac(?) and the wires well tucked in to fit withing the loco firebox. The tin of paint balanced on the front of the chassis is simply ballast to compress the light springs within the front bogie, to avoid short circuits via the brake blocks. Normally, this function is performed by the loco body.

Dave.