Equivalent Simplified Capacitor circuit
Here is some 'simplification of the circuit' 
That is the first simplification.







simulate this circuit &ndash; Schematic created using CircuitLab

The second simplification 







simulate this circuit

The furthest simplification, assuming C1/C4=C2/C3







simulate this circuit

Here are the results
C1+C4=C3+C2=C/2

nodes BC= C6+2*(C/2)=C+C=2C

I think I have drawn the circuit correctly. 
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