GuncCon2 on CRT with GroovyMame

[nix999]

Hi,

I got hold of a GunGon2 (edit: NPC106 from the year 2000 Japanese model and it looks as new actually) I want to get it to work with my GroovyMame realtime installation on custom Arch KMSRDM.
I have installed a Goobay/Wentronic 50312 between the UMSA and the TV and I have 'some' sync tracking through the composite video output. At least I think I have.
I installed drivers from psakhis that include a python calibration tool and if I try that tool I sometimes succeed in 'calibrating' it but I need to be very close to the tv. And that calibration tool is all but the correct aspect ratio et cetera.
In GM I am getting nowhere for the time being ... but I think my issue lies elsewhere ...
evtest registers all the buttons on the gun and if I sweep the gun over the screen it outputs data but I do not think it is as it should be.
I am aware that this post does not include details of my current setup and attempts but I can provide that if it could be relevant.
Now I just stumbled upon https://github.com/psakhis/guncon2/tree/main/linux that has an *.sh config tool. I havent tried it yet. I also found https://github.com/ZFEbHVUE/Batocera-CRT-Script.
I saw Substring and Calamity as contributors so I just wanted to ask before I try to reverse engineer the whole thing.

Is there any decent setup guide for what I'm trying to achieve?

I think my hardware is fine though in all honesty I am not sure ... It think the UMSA generates the correct sync signal as some of it's features mention:
- Composite Video Sync Generating by logic. Thus a wider range of graphic cards and TV are supported. This results in more stable signal as well.
- Jumper for negative and positive sync. Some signal needs a positive sync and some are negative. Configure here your needs.
But I do not know what that actually means ...

I'd be gratefull for any help offered.

Edit: it seems my hardware is bad . The UMSA outputs CSYNC and the Goobay (set to IN) just brings what is on pin 20 on the SCART out onto the yellow RCA - and the GunCon2 needs a proper composite video waveform with sync embedded at the correct voltage levels - whatever that means ...