Hi John S.,
We have replied to you in the support thread you have opened. For your convenience, please find below our reply:
Actually, due to the complexity of a Sitefinity page's lifecycle, you'll have the ScriptManager available in Design and Preview mode, but you'll need to adjust your control a little bit, so it works properly in Live mode. Please find attached a short video I've recorded while testing some of this functionality, and let me know if I'm missing anything. The only change that I've introduced is that I'm using a customized version of RajAjaxPanel which ensures that the Ajax requests will complete properly The custom RajAjaxPanel is built using the same approach as the one with UpdatePanel described in this blog post. For your convenience I'm attaching the revised version of your control and custom RadAjaxPanel along with the video.
If there's anything else you'd like to know or have some additional questions, please let us know, we'll be glad to help.
the Telerik team
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