I find my HDC is working well when in D , but the other day I was surprised to find it was not working properly, when in R. I can feel the pumping of the ABS, but there seems to be no forceful gripping of the discs-the FFRR just rocketed back down the slope, gathering speed.
Is this a software problem?
I have noticed that on fast mountain curves, involving heavy braking,( when I'm too tired to use manual and timeously shift down before the curve)on parking the car, there is much more brake -dust on the front alloys ,whereas the rear's are virtually clean.
Could these be related?ie is this a brake problem or possibly a defective body ECU?
I am also not getting all messages on the message centre. The FFRR would not start (Defect in the fuel system ,but no message in message centre.) The HDC problem is also not given in the message centre.The right side door mirror drops down and does not return, sometimes, even when the master switch is to that side ie not switched to the driver's side.
Are these electrical gremlins, or is the HDC a separate, mechanical problem?
Thanks guys for any help!

Lots of questions. Lets start with the HDC:
- first, having brake dust on the fronts and not the rears is normal. When you brake, weight is shifted forward (you lean forward too ). Most of the braking is done by the front brakes - this is why they are larger than the rears too. In theory you could have some sort of mechanical problems with the rear brakes (in reverse they do the braking) but without noise/other symptoms I doubt it. It is almost guaranteedly not a sw problem. Accelerating without wanting to is disconcerting - especially in reverse. Try a steep, paved incline and use HDC in reverse (I assume brake/ABS operation is otherwise normal). If your brakes feel fine otherwise, I'd guess you had a traction problem (mud/sand/whatever) and that made you uncomfortable. HDC is quite amazing - but bound by the laws of physics. If you heard the brake system modulating, you were slipping. If there was not enough friction (oil on the pads or similar) the system would not have modulated at all but continued to try to apply more pressure.
- message center: not all faults are displayed in the message center - and if you don't have a problem with the HDC it def won't be displayed.
- mirror: could be one of a hundred causes from a bad connection to a failing motor. Almost certainly not related to any HDC issues.

HTH 
RRC 2Dr, RRC 4Dr,
P38, and 2 L322s
(wife thinks I'm nuts - prob right, too)

Front and rear discs look shiny(no rust on rears) so in normal driving,I assume that the pads are applying pressure, but braking is, I feel a little "soft", not very abrupt.(Heavy vehicle? )
I tested the HDC on a slope which is not paved, but in D the car stopped dramatically and crawled forwards. In reverse, it shot back gaining speed , but stopped with normal foot brake applied.(It is unnerving when in R !!) If it were due to loss of grip, I think in D it would be the same ie rapidly gain speed. I have'nt carried out this test in low Range yet . I will try it on a steep grassy slope today( and the grass is wet due to a fine drizzle).I've got space behind me if the HDC acts up in R!
Thanks for the reply Steve.