Nope.
First, I had trouble figuring how to apply the Form Calc to the Button, as opposed to the Button List.
I actually had to edit the first line in the Script Editor, which seems pretty lame.
That is to say, I just don't see how to get to the radio button, not the Object named RadioButtonList
BUT, I can't UNCHECK the field once it's been checked. That is, if I click "on" the Radio Button, it won't revert to unchecked if I try to click it "off".
In other words, if the person unchecks the Radio button due to some error, I need it to click off and the TextFiled to go back to being hidden.
Like I said, this can't be that hard, or maybe I'm just missing what you're trying to explain. Any other ideas?
Steve