@escherize: as you have found, modal-panel does not support a backdrop click in 0.5.4 but will do so in 0.6.0 which should be released this week some time. The reason the content click closes the panel is due to DOM event bubbling.

Right. I decided to omit the feature and offer a bigger "Back" button.

Looks like I'll possibly double back at 0.6.0

fair enough, and shortly you will have the choice. Our initial thought was that it should be fully modal and not allow a backdrop click (after all, the popover allowed this), but we got another request for this feaure so went ahead and allowed it. If you don't specify the new :backdrop-on-click argument then it will behave as before for backward compatibility.