1. Create a network and added all Entities that implement from a specific ThingShape in the network
2. Create a ThingShape mashup as below
3. Create a mashup named ContentShape, add Tree widget and ContainedMashp in it
4. Bind Service GetNetworkConnection's Selected Row(s) result and Selected RowsChanged event to ContainedMashup widget
Note: Master can total replace ThingShape mashup. Suggest to use Master after ThingWorx 6.0
Can you show the screen shot of the end result of your Mashup.