I have been using my Akai MPK61 as a MMC control surface with the 32 Bit Version without issues.
Have started to use 64 Bit Sonar but for some reason it will not allow me to set up the MMC control surface in the 64 Bit version of Sonar.
When I try the MMC-1 surface comes up in parenthesis (MMC-1) and it will not allow me to select the device for midi ports. i.e. I can choose the Akai but as soon as you close the dialog it clears it.

Anyone have any ideas ????

Anyone using an MMC Control Surface in 64 Bit Sonar ???

Not the MMC but I have had the parenthesis issue trying to use a BCF Control surface written by one of the users here. I think it was bitman's adaptation of AJ's BCR plugin - can't remember.

Anyway I digress, the bad news is that the parenthesis means it's not compatible with x64, although having said that, I'm pretty sure my ZED-R16 is using MMC for the transport controls but I'm not at my DAW so can't check.

Thanks FastBikerBoy.
Thought that may be the issue.

Hello,
 
I hope all is well!
 
Did you ever find out anything about the MMC in the parenthesis? A fix or alternative?
 
Thanks much!

Use "Cakewalk Generic Surface" plug-in for MMC transport (read Reference Guide how to use it).
Dedicated MMC plug-in is long time obsolete.