Ok basically, the krazy karts project wont work properly if you join a session.
The Roles are the issue, checked by printing from the GoKartMovementComponent tick - in a regular game mode as per the course outline, it works fine in every aspect. The server prints as role Authority and Simulated_Proxy and moves fine.
In a session game as combined with the menu system, the server prints as role Authority only, and wont move. All throttle values will print as per the input. If you Create a move, and simulate the move, it will move, but then the client becomes jittery, and the server doesnt replicate to the client…
This system needs to be reviewed and updated with a fix