Found what seem to be a bug with the Hide Object When feature. Would love to see if anyone else can reproduce this before I report it. Also, a Goggle search didn't turn anything up for me, but let me know if this is already known.
Steps to reproduce:
1. Create new database.
2. Add a text object to the layout.
3. Give that object a Hide Object When calculation. (For test I simply used 1=1)
4. With that object selected, go to Button Setup via either right click or Formatting menu.
5. Add a button action (Single step or Perform script)
At this point, the Hide Object Calculation will remain visible through a tool tip, and seems to still function, but will not be viewable/editable from the specify calculation window:
Removing the button action does not fix the issue.
If the button action is applied before the Hide Object calculation this bug does not occur.