Hi Olga ,
Thanks for your interest in Syncfusion products.
I have tested this issue in v4.4.0.51 and the selected Link can be deleted when pressing the delete key. Please refer to the attached video file.
Video:
http://www.syncfusion.com/Product/uploads/Video_560bd08e.zipTest Sample:
http://websamples.syncfusion.com/samples/Diagram.Windows/F74770/maiin.htmCould you please check the sample and let me know whether you are able to reproduce the issue in this sample?. It would be helpful if you provide a sample or modify the attached sample to reproduce this issue. It will help us to resolve it as early as possible.
Thanks ,
Nagaraj