Sorry, I didn't realize the Play button already worked like that.
If I knew how to write an extension for it, I would, I knew I should have taken some programming courses in school, oh wait, that's right, there where no computers when I was in school
As for adding more channels, would it be possible to add a "Bank" command under the Select Slot - Midi Trigger?
If you select bank 2 then all the channel numbers would be transposed by 8, so channel 1 would become channel 9 or if you select Bank 3 then channel 1 would become channel 17 etc.