Interesting and configuration can be defined per game, but it will take time like everything else unless someone else has pre-made configurations you can harvest and implant with specific MAME or otherwise games.
I'd recommend test driving on one of your favorite trackball games and seeing what XML configs can be adjusted from the default configurations to perform 1 or 2 player options.
Please also note, my trackball and LED controlled by Ultimarc haven't been configured yet and so I can't provide any direct help.
Hopefully someone else will chime in and please update future posts when you learn or make changes that show success.
I'll look forward to future posts...
Thanks for contributing, Sorli...
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