I have researched this problem for a long time...
The Kinect approach seemed to be the fastest simplest approach (imho)
I purchased an original Kinect for cheap and a Nyko corrective lens and downloaded some free software (Kinect runtime v1.6 plus Brekel). Yes it works and the linkage to max is done through some simple plugins. However, the skeletal tracking is sketchy and requires a great deal of clean up to make the capture viable.
I was using a core2duo processor at first, but I there after used a i7 processor to get better responsiveness.
With improved software (which is available for a price) I believe that this process could quickly provide some decent animations.
That said,
The editing process is quite tedious and time intensive. After a long while of hacking, it became appearant that for the needs of Nwn1 it is easier to procedurally animate the geometry by hand (No school like the old school). The baked animations that occur from the above system are just too dense (keyframes) for realistic use in game. Considering that most animations are, in fact, tiny and singular motions that do not require intensive cpu processing. It became obvious that learning correct kinesthetic relationships was a better use of time.
With the above in mind, it is also my opinion that there is a "holy grail" of Nwn animation deep in the archives of Bioware (Perhaps lost to us for more than a decade). Since the geometry is animated directly, without the use of biped there might have been a process for converting or mapping the bvh files to geometry without the inbuilt restrictions of max. Rigging the character and importing animations is not enough. Using bones doesn't seem to the job either. Creating a animated geometry library, from which to mix required motion seems most viable. There might be a software, script, or plugin which can solve the dilemma but after years of searching I still have not found it, nor am I confident enough in maxscipt to write the necessary routine.
If any one can resolve this problem it might improve the workflow for animation.
Otherwise, learn how to animate realistically by hand and save yourself from the headache. One might actually enjoy the process of learning and come to appreciate the elegance of the real world in the process.
imho