The problem is, that the "Activated" sub of another form was fired after the overlay was closed.

We have found an issue when using the RadOverlayManager. We noticed that when our users have multiple monitors, the form Overlay shows in an incorrect position. In order to replicate this, set the scaling of the Main monitor to 125%

While using a RadOverlayManager to indicate a long-lasting operation, calling the  RadOverlayManager.Close method puts the main form behind the other opened applications. A sample project is attached.