Hi, I am using v2.1 of the webpart and SharePoint 2010 Enterprise.
The 'Filter' button is always disabled. I am working with SharePoint lists and GeoRSS feeds and get the same behaviour for both.
When I hover over the button the tooltip displays the message: 'You might not have the right permission level to use this, you might need to select an object or item, or the control might not work in this context'
I am a farm admin and site collection admin so I am assuming it is not a permission related issue.
I have tried to select a layer and a feature
I not sure about what context the tool should be used in