[@TK] oddly the 32bit edition that is out of date and abandoned from further development downloaded the same youtube video WITH the sound track file and merged it just fine… looks like the new current version 6.6.0 is broken for youtube dl in trial mode but the old 5.2.1 version dated from 5th December 2024 is still working but probably not with the giveaway license and not with only fans, supporting only spotify and apple music as premium sources and youtube and youtube like sources.
TK