This doesn't quite work. I still get "DataBinding: 'Telerik.Web.UI.Appointment' does not contain a property with the name X" error.
My custom appointment object has a custom AssignedTask object that contains the location info I wish to display.
I have added CustomAttributeNames="AssignedTask.LocationInfo", but that doesn't work.
Here is the template
<%#Eval("Subject")%> - <%#Eval("AssignedTask.LinkedLocationName")%>
The Subject works just fine, but I get an error on the second field. The datasource is being cast into a Telerik Appointment class, so these extra fields do not exist.