The slipping turn and the balance ball

[ozbeck]

I clearly have a mental block about this.

I can fly a balanced turn by applying rudder the same side as the ball. No problem. However, when it comes to understanding the theory I can not reconcile the following apparantly conflicting facts.

In the Trevor Thom example of a slipping right hand turn - the aircraft shown slipping into the turn is banked to the right and yawing left. In my logic, and understanding the further effects of controls, I would expect a banked aircraft slipping to the right to experience a yaw to the right due to the airflow on the fin and fuselage surface.

Also, when an aircraft yaws, what are the forces acting on the balance ball to make it move in the opposite direction to the yaw (thus indicating that 'same side' rudder will balance the aircraft)?

A bit nerdy possibly, but I like to understand what is going on, and hope that somebody can help me find the light switch here.

Waiting with eager anticipation!