Can't delete transitions

OK so I figured out what you're referring to. You're selecting the transition and then going into the menu at the top of the screen and selecting the drop down for Edit. This is not very intuitive at all. The "Edit" functions need to be available when a user right-clicks. I hope the Devs can respond to this and add a feature update.

UPDATE: So I figured out the problem. I'm currently using an Apple keyboard which has two 'delete' buttons. The 'delete' button on the QWERTY keyboard can be used to delete the transition but the 'delete' button on the button island with 'fn', 'home', 'page up', 'end', 'page down' does not work to delete the transition. This took me several hours to troubleshoot. Apple, in future software updates you should not only make all 'delete' buttons on your keyboard available to delete objects in the timeline but also make it so the option to delete is not greyed out when you right click on the transition.

I'm not sure where you're finding an Edit button for transitions in iMovie. I've looked all over this UI.