Install non-vendor image (kernel 6.12+)

[Jurgen.Schober]

I got a 6.1 noble minimal image installed with a latest kubuntu  update to KDE 6. Was quite some work to get this all working. But some thing aren't working (e.g. audio?). 6.12 and later supports a range more peripherals. I tried the non-vendor images but no  go. How do I install one of those? (Not using ROOBI, I hacked this to use my own)