this may help if you try to integrate Blogengine to provide Single Sign with another application that uses ASP.NET memberships.
I followed steps at http://msdn.microsoft.com/en-us/library/eb0zx8fc%28v=vs.100%29.aspx but it did not worked.
At last I found that BlogEngine modify its Auth cookies name to contain BlogInstance id. Each application had a different cookie and so they required separate login.
Look at this sourec file: DotNetSlave.BusinessLogic\Security\Security.cs:89.
After commenting out, it started to work.