I’m having some trouble when switching the scenes in mainly in the menu scene (but in all of them).
I used the logic bricks “set scene”. When I click with the left button over the Start Game (or other commands), it finishes the game or close Blender.
P.S.: I’ve made this on UPBGE 0.30.
In the past I was having some scene problems as well and I had to adapt to collections instead. There is some collections actuators that works just like the scenes, but it runs everything in your game at one scene.
The collections could be suspended/continued and added as an overlay collection, but you still need to set the main camera.