Well, that's another ball game entirely; I have never tried such a thing. I guess that every time you change a registration on the SD1 it will transmit a program change number on a given midi channel, but I don't think you can program also "which" number will be transmitted. In other words, Registration 001 will transmit always program change #1, registration 002 = #2 and so on... For what you want to do the only solution is a dedicated master keyboard or a midi patch bay.
In the General Arranger Forum about one month ago was posted a topic where the midi patch bay issue has been discussed at lenghth. You can do a search on that Forum using the keyword "midi patch bay". I think that the author of the topic was Zuki.
Let me know.
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