I also have a kmb-1 with the bx controler. I use Bobcad to write the programs and send them to the machine using a null modem cable hooked directly to the board inside the cabinet. On my machine there is a little switch on the back that has to be switched and then a little push button beside it that clears out the old program. After you do this, the screen will say "reading leader". You can now send a g-code program.
My upgraded bx board came from Accurate Machine Tool Services. It may be different than yours but if you need any further help just let me know.
Now, my parajust spindle drive on my machine just let out some smoke and now is dead. Do you happen to have any parts from the original parajust that you want to sell? Or possibly, do you have any information about upgrading to a more modern spindle drive?