Thank you for contacting us and for evaluating our WinForms controls.
Before answering your question, I would like to take the chance and advise you to use our ticketing support system for urgent requests. Please note that although we actively monitor our forums, they are intended for peer-to-peer support and replies from Telerik employees are not guaranteed.
To your particular inquiry, yes, I confirm that all trial versions display random trial messages. If you have developed a WinForms application with the trial version of our RadControls for WinForms, your end-users will see a copyright message every now and then. After you upgrade your application to the developer build, the trial message will disappear.
Please let me know if you have any additional inquiries. I will be glad to assist you further.