Adding Controltiptext to worksheets - I can make them appear, how to make them disappear?

By adding an invisible label over a cell, you can use its mousemove event to open up a userform that mimics a controltiptext.

The problem is making it disappear like a controltiptext - when your mouse moves away from the cell. Can anyone suggest how to do this? I have tried various methods without success.

Thanks.

anyone? Thanks!