Thematic Widget 3.6 with Flex Viewer 3.1

I want to upgrade my version of the Thematic Widget to 3.5 or 3.6 to get the ability to choose different layers. I am currently restricted to using version 3.1 and 3.4 of the main Flex Viewer with services set up in ArcGIS 10.1 SP1.

Does anyone know if I will run into problems mixing this 3.6 widget with and the older version of the flex viewer?

http://www.arcgis.com/home/item.html...b056cdcbdc9ad0