First of all I want to say thank you to all the developers, Mach3 works flawlessly for our "little" project we are doing (one axis stepping motor) and I am considering an upgrade to our anilam crusader using a Mach3 system. Very logically written and the vid tuts are incredible.

I can't get screen4 to do much, most of the functions I get a popup with a yellow emergency looking icon and I have to dump it with ctrl-alt-del.

I'm on a hopped up athalon system with Win2kPro. I'm going to try it on XP when I get home... does the OS make a difference?

I got the same problem the last day on the workshop computer, it had an old version of Mach3 on it so I downloaded the latest version 1.9 something and installed it. When I next ran screen 4 it worked great.
  One thing I have found is if you have screen 4 open with your current screenset and also have Mach open, if you edit the buttons script in Mach (only place it can be edited) all of the LEDs will go back to system function instead of OEM and I have to go back in screen4 and check all the LEDs as OEM. Easily solved by making sure I dont edit script buttons when screen 4 is open
Hood

Thank you very much for a speedy response, it worked great. Now off to make a dull boring single axis screen control-