Good to see that you are always on the ball with everything Smoke :)
I have got a MC Color and MC Transport panel in front on me.
Depending on how you have your caching set up in the smoke timeline will determine how the panel behaves. It is simply one hot-key or UI button on/off.
When caching is turned off all the reactions with the MC Color are real-time. When caching is turned on there might be a half second to second delay as Smoke caches up the change that has been done to the clip. Since Colour correction can be seen in real-time, caching is not really required but its up to you how you choose to work.
This is no biggie as switching the cache on or off really is one button and not an issue.
I would be interested in knowing where you read this about Smoke and the MC Color so that I may relay this information as well.