I've never used custom template for this control and I tried to do it and got the same error. It looks like the control isn't defined properly. But there is a hack which can help you, example:
<cms:CMSSearchResults ID="srchResults" runat="server" IngoneTransformations="true">
<ItemTemplate>
<a href="<%# DataBinder.Eval((Container as RepeaterItem).DataItem, "NodeID") %>">NodeID</a>
</ItemTemplate>
</cms:CMSSearchResults>
But the markup is too complicated and I think it will be better if you create a custom transformation and assign its name to TransformationName property (IgnoreTransformation property should be disabled)