>Did you receive the sources?

Yes, but didn't have time so far.

>Just tried same code in Delphi. Result - like always in Delphi - works perfect. I'm sure that it works in VC and VB as well as in Delphi. As for me it looks like VFP bug.

Well, before we find the reason, I wouldn't speculate. :)

>The Process screen is divided to two parts : left-hand side displays status of devices(weighing scales), right-hand side is for enter/edit order data for the devices.

Well, maybe you could have the robot process to run in one app and the user input on the other app, both 50% of the screen. :) Or, issue some kind of automation COM object being launched from the main app, where you would preserve the control from the main app, and maybe it would react better.