Thank you for reporting the issue. I have updated your Telerik points for your report. Unfortunately, while we are aware of the issue, it is very hard to reproduce and we are currently investigating the reason.
Thank you for providing information about your development environment; there are some other details that may help track down the reason and we will be grateful if you can answer the following questions: As far as we know from other our customers, the issue is always reproducible on certain machines. Is it so with you or sometimes the Property Builder works and sometimes not? In this regard, can you try to create a new project and see whether changes from the Property Grid are persisted and have you tested our controls on another machine? Is the issue reoccurring there?
Thank you very much in advance for your time. We hope that we will be able to address the issue soon but I cannot give you a time frame currently.
the Telerik team
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