Hi Michael,
There are some issues with using templates in nestedtables.We alreay have addressed these issues and we will be posting a patch version most probably tomorrow.
Where you can able to set the Item template in the aspx code as follows:
(Assume if you want to inlcude an ItemTemplate of Hyperlink in a nested column where the column name is "SomeName")
<%# Container.StyleInfo.Text %>
//Other Column Descriptors...
Thanks,
A.Sivakumar