1) This has been a bug which has been in the system since vs. 9. Any time you have a pop-up in the header and scroll out of view of the record you are on, the pop-up becomes unavailable. You can search in the Report A Bug for the specific link ... unfortunately I don't have time to find it for you right now.
2) You must use custom menus to restrict. Sorting is sorting all main records and not the value list. Value lists come as they are (ascending).
1. I see. Here are two threads I found about the issue:
FM 9 is three years old now and they haven't fixed the bug yet??? That's not a good sign...
2. I do use custom menus. It's just that I need the ability / allow users to be able to sort records, hence I can't remove the sort menu item. I just realized that the users can see the value lists also from the "Sort Records" window ("Custom order based on value list"). Is there no way to hide just the value lists from the users?