Hi Johan,
I think I stumbled upon a mistake in the picochess.ini file in the latest image.
In the beep-config section of picochess.ini (picochess.ini.example v3.2) the comment says:
"beep-config enables or disables the internal DGTPi beeper sounds or allows sound samples to be used instead. The options are "Never", "Sometimes", "Always" or "Sample"."
Using one of these options leads to Picochess not starting, producing a white screen.
The right options for beep-config are: none, some, all, sample
Hooray for 'systemctl status picochess'! ;)
Henri