EXTERNAL EFFECTS: automation not available???

Hi.

My system:
Cubase Pro 8.5.20 under windows 7 Pro 64 bit, intel i7, 16 Gb.
audio interface: RME Madiface USB + Ferrofish A16mkII + RME ADI8-Pro (= 24 analog I/O)
midi interface: Motu MicroLite

Problem:
external effects (hardware outboards) DO appear and work well as inserts in the track edit window, but DO NOT appear within the inserts available in the track automation panel, so that I cannot automate them.
Any other internal VST effect appear in the panel and can be automated but NOT the external effects.
What’s the issue?
What do I need to do ?

Thanks.

What hardware are you trying to automate?

no matter of the outboard: I have a few pieces of outboard hardware, like distressors, other compressors, pedalboard, a moog filter… each of them is plugged to a separate I/O of the audio interface (total 8 I/O dedicated to external effects).
Whatever I choose, it’s not visible for automation as channel inserts (only for the automation, while they are fully visible and working as effects on the track window).
what I would like to automate is even just the simple bypass of the inserted effect!..
Please consider that it is the same set-up I had with Cubase 5.1 under Windows XP and it has been working like a charm for years!
Thanks.