Apologies I didn't think that alternate layer rotation would mess up the 8 direction on another layer.
Another method would be to use the bullet behaviour and set to bounce off solids.
Set it to not change the objects angle and when you press a direction key you would set the angle to self.angle(+-desired direction angle)+Camerarotation.
e.g.
on left key down - Set bullet angle of motion to: self.angle-180+CameraRotation