Can't package game: "...has an inappropriate outermost"

Hah… this is really a “production-ready” product. Had the same issue… then I just moved something in the blueprint and hit saved and it packaged (btw I didn’t see any visible error in blueprint because the Play worked). Now that I have a package I have no input… although alt+f4 works lol… Would be nice if at least one straightforward use case was without problems