Check this out:
It will change the programs in both directions by +/-1 slot, CC 3 for up, CC4 for down. The trick is to produce 7 Note On & Off pairs to make the Dispatcher pipe go 7 steps forward, but as the maximum number of steps is 8, the end result is -1. The classic (i + 7) % 8 trick if only addition and modulo operators are available.
CC 3,4 bidirectional cycle.mhp (569 Bytes)