Thanks for your reply, but maybe you didn't read my post. As I already said, I can hide other controls using formatting rules with no problem, but the same formatting rules don't hide Calculated Value controls.
Here's my simple situation: I'm using a Calculated Value control to act as a Label for a Text box control so I can hide both objects when a condition on the form changes. The formatting rule correctly hides the Text box, but the Calculated Value control stays visible.
I'm looking for ideas what might cause this behavior and how do I correct it. I'm not having any other issues with this form.