I've posted developer 19.08.b. As always, bash away and let me know if problems. Major changes from 19.08:
The order of arguments in DEFGROOVE has been reversed. This change makes the actual code reflect the documentation.
-xNoCredit, -xChords and -xCheckFile have been added. Fun.
Bunch of debugging, manual fixes, etc.
Fixed summary to show midi file duration as mm:ss.
Changed -g message to Skipped from Existing
The options -xCheckFile and -xChords have been modified from 19.08a.
They now take their args separately. No = sign is needed/permitted.
The code for the zOPTIONS now finds the last chord. The docs for this section (Rests, section 8.4) have been rewritten.
Get it at: https://mellowood.ca/mma/downloads.html#developer