superheroic, I imagine the video is for a very old version.
The Mouse-Over tab is now in Utilities > Web Animation > Mouseover.
If you are there you will have selected an object (MouseOff) and want to perform some web effect to that object.
If you elect to Show pop-up layer, that layer must be something other than MouseOff or MouseOver.
You create such a layer in the (newly found) Layer view of the Page & Layer gallery.
A hover will now display the entire selected layer's contents.
On the other hand if you are just after a button rollover, you add another object to the MouseOver layer on top of the MouseOff object.
The rollover effect requies a large (50%) overlap and a Link on the MouseOff object.
When you drop an object onto the design page it goes into the selected layer (ticked in the Page & Layer gallery).
It really is a fine tool but you have to get to grips with its fundamentals.
Keep plugging and asking.
Acorn
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