The Custom command buttons are intended to be added in the dock's Commands
collection in the way it is demonstrated in the Commands online example
. The Titlebar of the RadDock is used for dragging the control and it is not intended to be used for adding Custom commands in it. Most probably the reason for the event handlers you mention not being raised when you add the custom commands in the dock's titlebar is due to drag handlers conflicting the ones you add.
The correct approach in achieving the desired scenario is the first one you have chosen. The problem you have encountered with one of the buttons falling below the title bar should be addressed in a different way. If you are not able to resolve it by yourself, please, open a support ticket and send us a sample page which demonstrates your exact scenario and reproduces the problem you observe. As soon as we can take a closer look at your setup and are able to reproduce the issue on our side we will do our best to help you.
the Telerik team
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