I've got a Mutoh XP-500 and after a very long time I finally found the drivers.
http://www.mutoh.be/page.aspx/152
I'm running XP and I'm currently trying to print from TurboCad. Just testing. I'm getting ready to work on some things and my plotter would come in handy.
Right now I can run a test page from the onboard computer system, but I can't run a test page from my actual computer. I'm running it from parallel and it has been suggested that I try a null modem adapter. I'm about to try that. If anyone else has any suggestions, I will greatly appreciate the help.