LC87,
A proprotional controller is equivalent to a multiply, so you could just create a transfer function with Numerator=[Kp] and Denominator=[1]. You could also use the CD Create PID Model (Parallel) with zero wired to the Integral Gain (Ki) and Derivative Gain (Kd). If you are going to implement this in a Simulation Loop, then all you need to do is use a multiply primitive.
Chris M