The tooltip should position itself according to its target in the common case and you can see this in action here: http://demos.telerik.com/aspnet-ajax/tooltip/examples/relativeto/defaultcs.aspx so you can compare the demo with your actual code. With the provided information the other ideas I can suggest are the following:
- set the RenderInPageRoot property to true to avoid inheriting CSS from its parents as much as possible
- remove the ClientIDMode=Static because the static mode is not supported
- increase the height to accommodate the content and avoid the space between the value and the "px": http://www.telerik.com/help/aspnet-ajax/tooltip-troubleshooting-common-issues.html - see the very first section.
- try the built-in skins, as it is possible that some customization in the MyCustomSkin skin affects its positioning.
I hope these ideas will help you resolve the case.
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