I forgot this!
This approach will go part of the way to what you are after:
Acorn
- Create your box or a new Layer in the place you want it to stop at.
- On the MouseOff layer add a clickable shape/button.
- For this, set its Web Properties > Link > Pop-up layer to the new Layer.
- Click its Settings... button.
- Change the transition to Slide in from left.
- Change the Speed to 5.
- Untick Close pop-up automatically.
- Click the OK button twice.
- Preview
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