Go to Activities and select 'Import'. You might want to read this http://connect.garmin.com/en-US/help/how-to/
I have same problems with classic layout, just blank page. And I have also Edge and it's big step for backwards if I have to upload every ride manually.
I have garminExpress already on my PC and it doesnt help anything.
What about 910XT, is classic layout working with that device?
Anyway, something have to do that upload is as easy as it was!