Simulink design LQR controller

I need control this model with LQR controller.

I implemented the cost function with:

x=[Pm w] u=[a] 
where, Pm is manifold pressure, w is the speed and a is the trhottle angle. 
First step I have linearized the model with: 
[a b c d]=linmod('Engine'); 
subsequently I use
K=lqr(a,b,q,r) 
where I choose 
q=[0.1 0 0 0;0 0.1 0 0;0 0 0.1 0;0 0 0 1] and r=500. 
I have create the controller block in this mode:

I have an errors for this block : Error in port widths or dimensions. Output port 1 of 'eng1/Subsystem/Gain1' has 4 elements. This port does not accept the dimensions (or orientation) specified by the output signal.

Someone can you help me?

Thank you so much in advance.

[Drill Be]

How did you define the system matrices (a,b, c,d), what are the dimensions? It seems you q and r matrices are not appropriate size with system matrices.