AJAX Control Library Accordion Problems
I had some problems with the Accordion control recently. I set it up similar to the sample in the toolkit that is included. It worked great; however, because I have server controls inside the Accordion panes, even though they registered in intellisense, I couldn't use them directly as is showing as available. I researched and found out that you can access the controls via AccordionPaneID.FindControl(), and eventually through AccordionID.FindControl(). However, I was able to get it to work, after calling FindControl on the accordion pane once, by using the control's direct reference, which was strange.
Anyways, this is something to think about and take into consideration when you design using this extender.