The Mach soft ware seems to be set  up for printer port  port and pin numbers , My DMB4250-8B Breakout Board supports both usb and printerport.  How do I designate using a usb port instead and what happens with the port and pin numbers ?  I am really a newbie in this area.      thanks,   Chris

The USB port on that board only provides 5V to the board. It's not used to send/receive data.

See pages 8 and 9 in the manual.
http://www.dmm-tech.com/Files/DMB4250-8B_BreakoutVer010106.pdf