Everytime I try to rout with a train track in the way i get this error (and now sometimes without):

The mod Belt Router (1.5.1) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event BeltRouter::build-transport-line (ID 187)
MiscLib/path_find/entity_routing_attribute.lua:311: attempt to index local 'splitterVersion' (a nil value)
stack traceback:
MiscLib/path_find/entity_routing_attribute.lua:311: in function <MiscLib/path_find/entity_routing_attribute.lua:290>
(...tail calls...)
MiscLib/path_find/entity_routing_attribute.lua:258: in function 'onGroundVersion'
MiscLib/path_find/entity_routing_attribute.lua:104: in function 'index'
__BeltRouter/transport_line_connector.lua:117: in function 'buildTransportLine'
BeltRouter/control.lua:166: in function 'setEndingTransportLine'
BeltRouter/control.lua:177: in function <BeltRouter/control.lua:175>