I have now added a certain number of midi styles I have found on the net to my own styles and they apear alright in my new styles list.
Of course when I want to hear them before loading them, I get the info that there is no demo for the style...

I remember that, in old versions of BiaB, it was possible to make a song and title it with the same name than a given style (mysong.sgu for mysong.sty) and then the demo song would open when clicking the style within the style picker.
It does not seem to work though with my 2021 version.
Any suggestion?/thanks in advance
Bernard