You may have to rebuild from scratch. I have an issue also when opening a game I've been building in beta 3 but note when building as new in beta 4 the problem is not apparent.
Thanks, you are right.! BB Team should next time keep this in mind, so that we don't have to build it from scratch again.!
Try emailing support@buildbox.com most likely there is no reason to rebuild from scratch. Sean can help locate the issue with your file.
thanks man.! But Buildbox was working so smooth that it was really fun rebuilding it. I had all the assets in place. Good work.! Kudos.!