Hey Reisn7CC,
Whether you created a Windows project on a Mac, or vice versa, you can more than likely expect there to be issues like the one you are experiencing. If you are moving from Windows to Mac then the externally referenced issues are definitely expected.
This is unfortunately not a bug, but the outcome following the workflow you are using. Mac’s use a different Shader Model and API so moving across platforms with those settings in tact is going to cause errors.
Config settings within the Engine and Project are going to conflict one another since you started on Windows and moved to a Mac. The only thing you can do in this case is to go one by one and locate the source of the externally referenced nodes and systematically resolve them.
If you have further questions let me know.
Cheers,