A blogger who was unable to add gadgets when in design (clicking on "add gadgets" takes me the blogger back to my dashboard page). Also, if he try from layouts, thru new template designer, all options are deactivated.
The blogger solved his problem quite simply in the end:
(1) adopted new template, and
(2), changed to mozilla firefox browser... "add gadgets" got enabled again...
Well if you have a similar problem, perhaps his experience can help you solve the problem