jammapi and low res template

[0zzy]

Hi all, i'm testing one new interface connecting jamma herness to arcade monitor (or scart crt tv).
It's jammapi.

It is only an hardware board, usable with any other arcade distros like recalbox and many others.
I was looking for a theme running nice with arcade monitor in low resolution.
Is there a guide to follow, if i want to edit the main recalbox theme ?