Hi,
Thanks for posting. Glad you were able to find a method of sharing a project with edits that works for you.
There should be no difference between using the File/Share/File method versus using the share icon to share (export) a project. Both methods should export with all edits intact. It is only when you share from the Project Media browser screen that a clip will share as an unedited clip.
Since that is not happening in your case, you might try deleting preferences and see if that cures it To delete preferences, open iMovie while holding down the Option and Command keys and selecting to delete preferences in the box that appears. iMovie will open in a new blank library. Close and then re-open iMovie in your original library to get back to your projects. Now see if you can share out (export) the project with all edits intact when using the File/Share/File method.
Another thing you can try is to create a new project and see of the File/Share/File method works correctly there.
-- Rich