To be fair though, it makes no sense that the "spindle RPM" box on the main screen lets you type a number in, but it does nothing. It had been long enough of a time gap that I had forgotten about all the quirk in Mach4 and how truly bad ArtSoft is at making intuitive and clean UIs. Sorry guys, it's true. You need to hire someone to help you make your UIs
.
To be
REALLY fair though, have you ran a Fanuc, Fidia, or Siemens? Or Linux CNC? Good luck with anything being intuitive with those. All things are relative.
What is it supposed to do when you put a speed in the spindle RPM box? Start the spindle? If so, which direction? Forward or backward? Would that be what everyone likes? There is
NO WAY we can make a screen set/UI that everyone likes. And there is
NO WAY we can make everything intuitive either. But we
DO give you the ability of making it exactly the way you want it.

We gave you a really good starting point though. Just modify it to your liking.
Steve