Hi Ron. I don't know a lot about the ACE but it has a hydraulic system to interact with the anti roll (sway) bars in addition to the rear air suspension.
You'll probably need a code reader to interrogate the ECU and find out what the problem is.
There may be a dedicated plug in reader available like the ones offered for my RRC, I think they were refered to as a "kicker" because they were used to reset the ECU fault codes but not reprogram them.
I do remember that on the Disco2 active suspension you can't program the rear height either, you have to set the current height as the default. One possibility is that the ECU can't get the rear end back to the correct or default height, possibly because you have loaded the rear end?
Have the load height sensors been removed?