Please check if your application pool gets recycled at the same time you try to make a request or somehow the role cookie gets cleared.
Do you have problems running the project locally? Through VS or Project Manager instance?
the Telerik team
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
system and vote to affect the priority of the items