Aerofab - I also have a Knee Mill (SuperMax YMC30) factory outfitted with Anilam Crusader 2.
First - you have to find out if the RS232 port is wired and active.
There is a code to do this - I can look it up if you like. Or you can call Anilam -they will tell you how to punch in the code and to read the output to tell.
After that - any simple comm program can Download to the mill or upload from the mill. I use BobCAD Cam's built in Communication with a PC (2400 baud, 7-n-1) with absolutely no problems.
As for pure DNC - as in dropping a chunk of g-code at a time to a running Anilam - I'm told mine cand do this - but I have never been successful.
I am going to convert the whole thing to Gecko 320 based controller this fall.
Drop me a line if you have questions. Also email to Joe(atsymbol)BigWoodVise.com