Changing height of each wheel sensor with PIWIS2

[ciaka]

Does anyone on here have experience with changing height of sensors for each wheel separately?
I have been trying all day and cannot get them to adjust just the way I want to.  
The height is measured from center of wheel to bottom lip of wheel well fender (straight line from center of wheel).  It is so for all 4 wheels.
The default height for front wheels is 404mm +/- 10mm (variation in height left to right)
The default height for rear wheels is 406mm +/- 10mm (variation in height left to right)

The closest I get is have one side perfect, and the other about 5mm too low or too high.
As soon as I get into PIWIS2, and make the changes, the sides misalign again, and one side goes too low, while other side goes too high.
Frickin frustrating.

What I use is the LEVEL/PASM main menu in PIWIS2.  Then enter Maintenance Repair sub menu.  Then select the height sensor calibration sub menu.
While in there, the screen shows all 4 corners, FL, FR, RL, RR, each on separate line.
To make the change, one is supposed to measure from center cap to bottom of fender lip (as stated above).  Then you enter value in mm for each corner, then click WRITE, to set the settings into ECU.  Then you turn ignition off, then on, then press F12 on screen to finalize the setting.  Clicking on write performs write of all values, all at once.
I changed the valve block and refreshed one shock (that was leaking internally).  With the new parts in, wanted to make sure all corners are just perfect before I do alignment again.
But this thing is testing my patience.

Some of the questions I have are:
1.  Am I even supposed to be using the sensor height calibration menu to set height of each corner separately, or is there different menu where I would code the setting of one wheel for example (the above sets all 4 settings together, with click of the write button).
2.  To lower a corner, say by 10mm, I have to be in the menu with all measurements, then I add 10mm to existing number (i.e, if setting for FL is 400, I calculate 400+10 = 410 mm, which is supposed to lower that FL corner by 10mm).  AM I doing this correctly?  
3.  Is there a specific process for the calibration, meaning I have to set the height to predefined height to store in ECU, then make adjustments?  

What am I missing?  I have been going up and down and cannot get the thing right and hope one of you folks have done this. 
I dont get any errors at all, even when doing component test before doing sensor calibration.  So all my hardware is working properly.

Thanks for help.