I did a custom control that i use in the Veristand workspace.
When the workspace freeze (I don't no why) the VI get fault value send a error (74). So i must filter error 74 in my custom control.
I think it is a bug in NI VersiStand 2011...
I filed CAR# 346665 regarding the error 74 you are receiving.
One question I had was: Does this Workspace freeze you are seeing happen if you don't have that custom control on the screen? How often does the freeze occur?