I want a common footer to run through all the various layouts I am creating. This will be the menu bar.

I also want to have a button that shows "Switch to Admin mode" that disappears when clicked on (and the user is put in admin mode) to be replaced by a different button (I DON'T just want the text of a button to change) that says "Back to standard mode".

How do I make a button invisible ?

If your footer is truley a FMP Footer you can not use the trick of hiding elements with a portal because portals do not work in any other parts except the body.

What you need to do is create a global field set as a container perhaps repeating.

then place your "button" graphics in each one

the you need to create a global number field

then a calculation field that says:

GetRepetition(Graphic Field,Number Field)

Then place this on your layout. Then you can create a square or object over the button as a mask. Then make it filled to none and no lines. Define a script to that button which based upon the Number Field performs a different script, ie Toggles back and forth between your layouts.

This is usefull if you want to preform a different script dependend on the contents of that record. The only down side is if the graphic is blank the button will still flash at you. Although it won't do anyting.