Well the results are in. The only way to get album art to display on the console is to embed the art within the mp3 file when using a USB drive. I had to use mp3tag to load the album art I had in each album folder and wait forever for CUE to reindex
this might apply to one of your questions. CUE went berserk when I tried playing my .mp3 music from my ripped files written to USB/SD/CD...specifically the file structure and about 50% of the files were not recognized. retried in a new 2014 CTS Premium (because I figured CUE (the 2013 rev) could be to blame) and the major symptoms were the same!
after much screwing around and surfing, as an experiment, I changed from this original file structure:
album 2, etc
to this where all album folders are in the root:
album 1, artist whatever
album 2, artist whatever, etc.
now CUE at least sees all my files.
still aggravating: it often displays (and plays) two or three iterations of the same track. it's occurred to me that maybe I need to research how to re-index/initialize CUE. I received no info up front that CUE had any internal memory but apparently it does. tracks I've erased and then re-written on a newly-formatted SD still appear as multiple entries in some cases. WTF? my $15 .mp3 player has no difficulty with multi-layer file structures or replicating tracks from new media using stored data!