Finally, I got it all working without any flaw.
This is the setup of the control area with the X32 mixer, 2 laptops, 1 extra screen, the midi connection and the dmx controller.
All this needs to be controled by one person (me...):
Remarks: I had to split the DMXControl GUI from the DMXControl Kernel to have no errors any more in the workflow. I suppose that the load on the old Dell 5500 was too much at some random moments.
With this setup I can keep an eye on the progress of DMXControl 3 although I had no problems anymore yesterday and today on deep testing.
The second Laptop (Dell Ivan) sends the DMX commands out, records 25 multitrack from the X32 and via a second display I can also keep up with the scenario.
I know, much to do, but I can manage this thanks to the effort I put into making the midi work and the split setup of DMXcontrol over a dedicated network connection (I had the router available anyway for remote control of the X32 in my flightcase).
About my suggestion for a midi logger in the previous post: I think it is still valuable, but I managed to configure the 'Midiview' app in a way that it sits between the midi interface and DMXControl without disturbing anything (only for debugging reasons). I could observe that DMXControl effectively, at some random moments, misses a midi note message. I could never determine with certainty what was the cause. As I said, I think this old laptop, running on windows 10, may be having performance issues rather then DMXControl having to blame. Running everything on 1 laptop (Dell Ivan) was no option too since I need 3 screens to get visualise everything I wanted (and eventually intervene when needed).
I hope someone finds this information usefull or not ... I think this feedback has his merits anyway.
Thank you for all the help. I'm happy all works fine.
Sad to say ... but the 3 gigs are suspended again for covid-19 reasons in the local community. The work is done, I'm ready now.