Thanks for your interest in Syncfusion products.
Essential Diagram WPF currently does not provide support to customize the selection rectangle. This feature will be provided in our future releases.
The center port displayed on each node is for enabling connecting to the nodes boundary in case any other ports are defined on the node. However we suppose that you wish to hide the center port when the node is selected or moved. We will provide this feature in our future releases.
We usually have a timeframe of at least three months between releases. The feature
implementation would also greatly depend on the factors like product design,
code compatibility and complexity.
However the line connectors are completely customizable. Please refer our online documentation for further details.
The online documentation can be accessed via the below mentioned link:http://help.syncfusion.com/ug_72/diagramwpf/defaultWPF.html
Navigate to : Concepts and Features--> LineConnectors
You can define custom ports on the nodes to make connections to specific points on the nodes.
Navigate to : Concepts and Features--> ConnectionPort in the online documentation to get more details about how to define custom ports.
This way you can change the point at which the connection is made to the node. By default the connection is always made from the node's bounding rectangle.
We have noticed from your previous responses that you have a license for Essential Diagram WPF product. Therefore you might like to know that you have an existing personal Direct-Trac acocunt available using your own email address, and we highly recommend using your personal account. You'll get a faster response along with an automatic update when your question is answered via DirectTrac, and you can login and view your incident history 24x7.
Simply visit https://www.syncfusion.com/Support/DirectTrac/logon.aspx?URL=/Support/DirectTrac/default.aspx to login. If you have any further questions, we hope you will take advantage of your existing account and available services as a license holder.
Please let us know if you have any concerns.