Im not familiar with apple software either. Im just answering the question regarding where the conversion function might be in foobar.Sounds good, but how would that get him track splits or a cue file, LMQ? He's starting with an album length flac file and no cue.
But...IDK about anything Mac.
The whole conversion process here seems like it went wrong early on. What is quite easy on a windows system seems to become overly complicated and troublesome when you are restricted to OS.
This started out as a ripped iso from a blue ray disc. The XLD conversion that was done should have had an option to split the tracks from the start when the conversion to FLAC was undertaken. I dont know if it actually does that or not, but it should. Until this issue came up, Id never even heard of XLD.
Thinking about how to do it from the start maybe you could use makemkv and DVD audio extractor . Both are available for apple. Makemkv would disable the copy protection, and Ive heard of guys making disc backups with mkv to do just this. With the protection removed, DVDAE will split and convert to flac. Again, im just theorizing here. It all would have to be tested.