If a CmpMap's component Mappings are joined in series, then
its Nin attribute is equal to the Nin attribute of the first
component (or to the NoutNout attribute of the second component
if the the CmpMap's InvertInvert attribute is non-zero).
If a CmpMap's component Mappings are joined in parallel, then
its Nin attribute is given by the sum of the Nin attributes
of each component (or to the sum of their Nout attributes if
the CmpMap's Invert attribute is non-zero).