You can use auto generated symbol method, but you have to enable Include Entire File and choose B40K440 as subckt in symbol creation. Your simulation not working as you choose SIOV, but SIOV is child sub-circuit and B40K440 is parent sub-circuit. Schematic should call parent sub-circuit but not child sub-circuit from a library.
Or, here is to use user created varistor symbol and with .lib method to call the subckt from library. (.lib file put into same directory as .qsch).
B40K420.qsch (2.1 KB)
