I reckon it all depends on whether Noel and Cakewalk still have any interest in keeping CS functionality alive because the vs700.dll (and the MCU stuff) is probably already considered legacy code and (most likely) not update to date with what it takes to make it work with X2/X3/Xn.
From what I've read in various threads the MCU control was once done by (sort of a) 3rd party person. So it should be possible to understand, maintain/fix and eventually extend the functionality from outside - if reasonably documented and not yet spoilt by weird quick fix hacks (seen that in companies where I came in to work on "legacy" code).
It definitely takes a good deal of dedication to get this off the ground - and to make it last, it would require (a) continued interest from Cake, including a knowledgable contact inside Cake that answers questions and (b) the source being truly in the open source domain, with source repository, release management, etc. because the trouble with a one man show is that once this guy gets other important issues or loses interest its all dead again instantly.
Another questions is whether there is any overlap between the VS700 and the MCU (and if it was properly designed there must be loads of overlaps) because if it affects also the MCU you have a whole new game i.e. potential for combining both controllers (extension to the VS700) but more importantly quite a few additional users with MCU, X3 and software development background ...
(however, i was asked by fellow users not to bring the discussion over the X forum quite yet until we hear from Cakewalk ) Well, as usual - it's all open until someone from Cakewalk chimes in. So let's hope X3 starts off smoothly that someone finds time to think and talk about this ...