Incidentally, for anyone following this thread and trying similar things, I wrote a minimal python3 script to expand all .wma files below it to .wav files.
I'm sure it could be more efficient in execution, but it worked OK for me. It takes some time to expand an UltraPAK. Named expand-wma.py3, made executable, run by ./expand-wma.py3 I've added a .txt to enable upload.

Caveat Emptor.

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Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2024 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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