This is sort of a radical suggestion and I'm not sure if it would flow, but what if there was a central "Edit Bundle" at the top which included (at the bottom?) the Resources (should you want to add / remove / change them), as well as the quicker "Edit Resource" button per resource? I think it makes more sense and is more user-friendly to have a central "Edit Bundle" button which lets you alter all aspects of the bundle, not just the description and details.
I don't think you should have to click Edit "two levels deep", I think by default "Editing" a bundle should bring up both current interfaces (Details & Resources). Meanwhile the bottom "Edit" should be a shortcut straight to resource editing in case you don't want to mess with the details / description / screenshots / etc.