I believe that you are correct.

That would work for setting up Smart Macros, and I can in fact control via the Smart Macros (on ports 1-12), but that requires dragging each macro (in this case every command I would want to send, ch+, ch-, etc, etc) into the MX-3000 editor via the Universal Browser.

I don't believe that the "IR Passthrough" will work, which is what would allow me to keep the current configuration and move the macros on the 3000 to the MSC-400. The passthrough would send the IR commands stored in the remote via RF to ports 7-12 if you set thr RFID to > 10 (which you cant in the MX-3000 editor).

Thanks for checking, I appreciate the feedback.