Hi Pat
I am assuming you are using the Interface Gauge gadget in Workspace Studio. Am afraid, there is no option for what you are requesting. i.e change color or flash. The best what the gadget can offer is for the user to modify thresholds, which will increase or decrease the yellow and red indicators/meter on the gauge.
If this does not help in your case, I would recommend to file a feature request on thwack and we will track it from there on.
Thanks
Cliton Godinho