Hello Gernot Oberhammer,
Thank you for contacting us.
The control properties should not be changed after upgrade. There could be changes to the template properties because we use embedded templates from Sitefinity version 3.6.
i get nothing since the path of the picture is parsed wrong - but why?
Could you tell us what is the working url, because we only see this one that does not work and cannot compare it with the working one. Any additional information will be appreciated.
the Telerik team