I answered in your support ticket, but I will copy the answer here, as well:
The reason for the error that you are getting is that the template is searching for a property that does not exist, probably because this is the template for another content widget (of another module) and it is wrongly applied to the current widget that displays content from another content type.
On the dropdown list - we are aware of this bug and it will be fixed for our next release. I apologize for the discomfort that this caused.
the Telerik team
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