Let me get straight to your questions.
1. There is no MouseOver state of the RadDiagramShape object by default. Could you please be more specific on what exactly you need to customize? Maybe sending me a picture will be enough to understand what your requirement is.
2. You are on the right way. To achieve your requirement you can control all the connectors of a shape using the RadDiagram.Connectors collection. To clear all the connectors you can invoke the Clear() method of the collection. You can find more information on that matter in our Custom Connectors article
On the other hand, I have the feeling that our Gliding Connector feature will be suitable for your second requirement. You can see how this feature behaves in our Class Diagram online demo
. Note that the connection is not fixed to any connector. Rather, it always points the shape and moves along if you change the position of the connected shapes. You turn on this feature by setting the RadDiagramShape.UseGlidingConnector property to true.
Please try this out and let me know if you need any further assistance.
Pavel R. Pavlov
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