It was a little nightmare of missing packages in the Libreelec 10 mirror, drivers not compatible with kernel ver. 5.17.9 etc., but in the end, and with almost zero linux knowledge in about 24 hours of work (with the help of a small web server created ah-hoc to let compiler download the prepared compatible packages ecc.), I was able to compile a version that worked with Jasper-Lake CPUs and related GPUs, wifi ... are small satisfactions.
If anyone needs this version, or wants to make it themselves ... write me.