I've created a patch for mt32d and xmt32 to allow selection of either the MT32 or CM32L ROMs via command line switch. Hopefully it will be useful for others as well. Please let me know if it looks reasonable or if you'd like changes made. I'm hoping for convenience that this kind of functionality can be mainlined.
Edit: The patch had an inconsistent setting between the mode default (int mode=2) and the usage notes (CM32L is the default mode). Either mode should be initialized to 1 or MT32 should be the default. This version is corrected for the error.
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