I got a Nyko ZOOM for the Kinect in the mail today from Amazon for $6.99.  These are my results so far.
It advertises as 40% less distance the kinect should still work.  Here are 2 images :

First with the ZOOM. This the the depth image - the "important" one in my mind :)
You'll notice more black holes (no depth info), additionally there is an outer ring of darkness and the image itself is more distored.  That's the bad news... the good news is my hand is at only 12" from the kinect.

Here is without the lenses.  Less black spots, less distortion, but  the closest I can get my hand is 21" after which there is no depth info at all.

Conclusion : 

There are some challenges to contend with, but is it worth $6.99. Definitely!
If the project is to map out the room, I would prefer to do it without the lenses, but it might just address the InMoov's  "I can't see my own hands" issue .. If he could see them then it might be possible to self calibrate without using other strategies such as optical TopCode.  Although Topcodes might be usable at almost any range..   Someone with an InMoov should put some sticky tats on :)