Today i tested the Morningstar MC8 which i just received, nice piece of equipment.
While trying to program it to choose the slot in performance mode i discovered this:
When using CC #50 to #54 to chose the slot, you have to put a value higher than 0 or it won't work. It took me some time to figure this.
I haven't found this information in the main manual.
In the midi manual it's written that you have to use value 1, but it seems to work with every value that is not 0.
It would be probably a good idea, either to write this info in the main manual or (better) to change the CC so that it accept all values (although there is perhaps a reason i failed to see for this to be like this).