Custom blocks from the Web

I found a very cool custom block called MathScript on the NXTasy.org web site.  It actually does high-level math by operating on text scripts. 

I've downloaded it to one laptop, and I think I put it in the right location, but the NXT development application can't find it.  There is a patch available to add the import/export block capability, but even after applying the patch, I can't get it to work.  A question to the NXTasy.org forum may bring me an answer.