  We study the propagation of solitons on complex chains built by inserting
finite graphs at two sites of an unbranched chain. We compare numerical
findings with the results of an analytical linear approximation scheme
describing the interaction of large-fast solitons with non-local topological
defects on a chain. We show that the transmission properties of the solitons
strongly depend on the structure of the inserted graph, giving a tool to
control the soliton propagation through the choice of pertinent graphs to be
attached to the chain.
