Hi,
I recently switched to a new 64 bit partition after years of running SONAR 32 bit. Everything appears to be working except for MMC commands. In 32 bit X3 I have it working fine, receiving MMC from my Yamaha 01v96i without issues. The setup was pretty simple in 32 bit as well, just add a control surface, and select MMC from the drop down, assign ports & channels and it just worked. Problem is there is no equivalent control surface in the drop down in X3 x64. I have messed around with this for an unhealthy amount of hours and I don't appear to be getting anywhere. Is anyone able to point me in the right direction, perhaps a control surface template import for MMC? Thanks, much appreciated.

There was several discussions about MMC plug-in, which was 32bit only.
 
You can try to use Generic Control Surface plug-in, but there is no ready to use preset. Add it with Input/Output configured the same way you did with MMC. Open its property page. Select "Play" in the "Global Parameters". Press play button on Yamaha. Press "Learn" button in the plug-in. In case everything is fine, you should see "SysX Trigger" selected  and something like "F07F..." in the "Trigger Messages" and the button (on Yamaha) should Play/Stop sonar. Repeat the sequence for other buttons.
 
For complete documentation, see Chapter 40 in SONAR Reference Guide.

Thanks for the response - much appreciated.