Have you checked if minilab output the midi cc messages you set? There are toolls that can show the midi output.
If you are on Windows you can use this:
http://www.midiox.com/Also are you sure you have set up your controller correct in Live?
Minilab MKII has a memory set up for Live. Does that work?
And can you control plugins with midi cc using encoders?
It will be strange, if Midi CC does'nt work, when the settings is in MCC. But perhaps the thing you need to do requires more than an on/ off message? Can you do what you wan't using an encoder?
Just some ideas to troubleshoot.
Please keep in mind, that you can contact Arturia support through your account.