Concerning conductivity of dielectric coatings the corresponding conductances (surfacic and volumic) are automatically computed when you turn on these conductivities.
You only plug an extra resistor if you physically have one in your system (a physical electronic device), e.g. a decoupling resistor between solar array ground and SC chassis ground.
So you should know about it!
JF
PS: in principle what I just explained is already explained in the documentation