OK, I have read in this thread that there are problems with the MMV crashing. That is pretty ambiguous. The original post asks Arturia to fix it, but you haven't given them a starting point. When asking for help, include the following.
(1) System specs including Platform (Mac/PC), Processor, RAM, OS (including Service Pack level if applicable), MIDI Interface and / or controller, and audio card.
(2) Version of the application
(3) Mode you are using the application in (e.g. Stand-Alone or one of the plug-in modes)
(4) If it is a plug-in mode, the host application you are using it with.
(5) A detailed description of the crash, including error messages and symptoms (e.g. lockups, poofs, etc.)
(6) If possible, a step by step procedure to reproduce the problem.
I am sure that Arturia will be able to do more with this than simply saying that the application crashed.