I moved a Blueprint from one of your examples over to my test project and saw a bunch of errors on startup where it couldn’t find this and that of the blueprint (because I made a different folder structure). My suggestion is to give us an option to find the missing pieces… a browse button beside each error so we can help Unreal find what it’s looking for and fix it’s paths.
Did you use the migrate command or moved them by hand?
I moved the by hand… like in Win Explorer. I don’t know anything about the migrate command… I’ll google it.
Aha! I just found the info on migrate… I’ll use that from now on. 
Thank you !