* This allows playing around with instances directly on the canvas instead of relying on the actions to flip or change opacity and needing to start a preview
- Custom objects like the 3D particle emitter can be used as any other 3D object
- with the same set of actions and conditions thanks to the 3D capability
- in the scene editor, their Z position and 3D rotations can be changed
- Fix child creation in `doStepPostEvent` function
