Learn cc Cubase 9.5

Hi,
The Learn CC function in various VSTi (eg Halion or Retrologue) does not seem to work for CC# below 78. I tried with both the Retrologue 2 and Halion SE, and it works for values greater than or equal to 78, but nothing happens for smaller values. I checked with a MIDI monitoring software and the correct values are indeed sent to the computer (Mac Mini - Mac OS 10.13.14). I have Cubase Pro 9.5. Can anyone confirm and tell me if there is a solution ? Thanks.

Correction: the problem seems to occur for values between (incl.) 70 and 77.

I managed to fix the problem by assigning the values in Studio/Studio Setup/Remote Devices/VST Quick Controls/Address to 127. I am not sure what these are for since nothing happens in the Quick Control view of my VST Instrument when I send values to these controllers with the external MIDI controller. But now I can assign values from 70 to 77 normally.
As an example, now if I turn a knob on my physical keyboard (used as external MIDI controller) assigned to controller 74 I can see the cutoff controller in the Retrologue (which I "Learn CC"ed previously) moving accordingly, but nothing happens in the Quick Control view…
So if anyone can explain this, I’d be grateful. In any case I solved my initial problem with that workaround…

Ha ha this is getting fun… Now if I set the values back to 70, 71, …,77 in Studio/Studio Setup/Remote Devices/VST Quick Controls/Address it works in BOTH the VST instrument view AND the Quick Control view. So I guess there is a bug which prevents this to work if the values are already assigned in the Studio/Studio Setup/Remote Devices/VST Quick Controls/Address window. So to summarize:
To Learn controllers with an external device using controllers already assigned (but not working) in Studio/Studio Setup/Remote Devices/VST Quick Controls/Address you need to:
1 - set Studio/Studio Setup/Remote Devices/VST Quick Controls/Address values to dummy value (eg 127)
2 - use the normal procedure to Learn CC in your VST instrument
3 - re-assign the original values in Studio/Studio Setup/Remote Devices/VST Quick Controls/Address
Now you can remotely control with an external device the assigned controllers both in the VST Instrument view and in the Quick Control View.