Yeah, it appears to be something template-specific. I tried packaging a First Person C++ project and it worked just fine. I then tried the Third Person Blueprint template again, but this time added some custom C++ classes. It packaged and played without issue. So it seems to only be certain C++ templates that are not working. Maybe something screwy in how they coded the example Character, I guess? In the meantime, I guess the workaround is to start with a Blueprint project and then add C++ classes to it.
I’m wondering, has anyone been able to successfully play a packaged UE5 Third Person or Top-Down C++ project?