Resize predefined shape geometry?

Hi Peter,

 Thanks so much. My first issue has been resolved. Now the vertical line is not showing in the RadDiagram. But the second issue is still there. It is still showing the small tab at left-upper corner. 

I also want to remove the border of RadDiagram. There are so many line showing around the RadDiagram. Attached snap-shot is showing my xaml code and the output. Please have a look into the snap-shot and let me know the solution of my problem.

 Thanks

Rahul