Hi Fred
Does the MFC10 tell you what note number (and velocity) it's sending to do the Page +?
The note numbers sent by the MFC by default should be documented in its operation manual (you may change this configuration). The Tyros series supported a MFC10 template that was compatible with the default setup of the MFC10, so it was a no-brainer if you used the standard setup chosen by Yamaha.
The Genos does not have such a template, but the standard setup for the "External Controller" page (go to Menu2 / MIDI / External Controller) may correspond to the default MFC10 setup (not sure here...).
Anyway the Genos default setup for External Controller does not offer Page +/-, so you have to choose two MIDI notes of your liking and set its function as desired (Text Viewer Page + resp. -). This way you can use any external controller to scroll the pages by sending MIDI note on events or (which was not possible with Tyros) control change events.
OK, but couldn't I create a midi file which sends the same Note On command (if I knew what it was)?
Well, yes and no. The problem is that "external controller" really means EXTERNAL controller. The MIDI events really have to be received at a MIDI Port, so it will work with an external sequencer sending its data to Genos via MIDI Port A, B or MIDI USB. Genos will NOT respond to a MIDI channel from the INTERNAL sequencer (unless the behaviour of Genos is different from the Tyros series). A possible solution would be to use a MIDI loop back, so the internal sequencer sends out a Note On Event on one MIDI port while the second MIDI port is listening to this channel and is setup as the receiver of an external controller.
Hope my description was not too confusing
and coukd be of some help.
Michael