Hello!
Thank you for bringing this issue to our attention. We were able to reproduce the problem with the RotateTool and have logged a fix. The next update of Essential Diagram will ship with the fix in place.
For the time being, please use the attached CustomRotateTool in place of the standard Syncfusion.Windows.Forms.Diagram.RotateTool class to work around the problem. To use this tool, first unzip and add the RotateTool.cs file to your application. Now within your application initialization code after creation of the diagram control unregister the standard RotateTool from the diagram Controller and register the custom rotate tool in its place. The appended code shows how to register the CustomRotateTool with the diagram Controller.
// Unregister the standard RotateTool and use the custom RotateTool
Tool rotatetool = this.diagramComponent.Controller.GetTool("RotateTool") as Tool;
this.diagramComponent.Controller.UnRegisterTool(rotatetool);
this.diagramComponent.Controller.RegisterTool(new CustomRotateTool("RotateTool"));
We apologize for the inconvenience caused by this issue.
Regards,
Prakash Surendra
Syncfusion Inc.,
RotateTool.zip