Mark,
I may have tunnel vision. If when you swap the outputs for the spindle and coolant the spindle works as it is comanded, change them back and the coolant doesn't it has to be something beyond the control of Mach. What is different about the way the spindle is controlled Vs. the coolant? The spindle is on a relay, the coolant is on a selonoid etc.? If a light switch operates one bulb and not another it has to be the bulb right? Not necessarialy. One may be 12VDC and the other 110VAC. I know this has you at your wits end, I'm there with you and I'm 1500 miles away. I have been whiped before, but never by a machine. Stumped yes, not whiped. I won't give up if you don't.