As I stated in the work item comment, the problem is that I gave you a bad advice in my first post!
The naming convention for Actions will try to associate elements in the view with methods defined in the
associated view-model; since no Save method is defined there, no convention is applied, and thus no ActionMessage is created. That said, even setting the Target has no meaning (there is no Action needing a target).
The second code snippet I provided is indeed the answer: you must specify both the target and the Action, since you cannot rely on the convention.
My bad for not paying enough attention --'