running mach 3 with a usb to parallel adapter

[paulus.v]

Is there a setup guide to interface mach3 to the uc100

It you followed the UC100 setup guide and have both leds lighting continuous, then the rest is to configure mach3 to communicate with your machine, setup ports and pins, motor tuning, etc. Probably your cnc came with a mach3 profile file which you need to load.