Replying to RAR archive in parts

So, I'm trying to install a program that I lost my install discs for (NI kontakt).

I have downloaded an installer using torrents, and now I have a bunch of files.
They're named :
d-k41m01.zip
d-k41m02.zip
d-k41m03.zip
d-k41m04.zip
d-k41m05.zip
d-k41m06.zip

etc etc up until d-k41m49.zip

There is also a "file-id.diz"

Im on Mac OSX, all my software has been updated recently (no Lion).

Does anyone know how I can take these files and get this program on my computer?
I know it has something to do with an archive broken up into parts, but I don't know how to recombine it.

Thanks NS!
+karma to all who help.