No, it's not assignable.
There are six modes. Some are standard midi CC, some
for soundfont equiped Soundblasters, Yamaha XG and Roland modules.
If your
software has a learn mode, you can probably use it in it's Standard CC mode as it suits
you. It has a send snapshot button so you can get the application synchronised with the
knob positions.
This shows the controls...
http://www.keyfax.com/keyfax/prdct.html
...look under
hardware controllers.
Hmmm... never heard of the "Flat Boy". Anybody got one
of those?