The Miniloader mod (1.15.6) caused an uncorrectable bug.
Please report this bug to the author of this modification.

Error while running event miniloader::on_robot_built_entity (ID 14)
miniloader/circuit.lua:83: attempt to index field 'split_lane_configuration' (a nil value)
stack traceback:
miniloader/circuit.lua:83: in function 'sync_behavior'
miniloader/lualib/miniloader.lua:156: in function <miniloader/lualib/miniloader.lua:137>
(...tail calls...)
miniloader/control.lua:112: in function 'handler'
miniloader/lualib/event.lua:15: in function <miniloader/lualib/event.lua:13>

and

Error while running event miniloader::on_built_entity (ID 6)
miniloader/circuit.lua:83: attempt to index field 'split_lane_configuration' (a nil value)
stack traceback:
miniloader/circuit.lua:83: in function 'sync_behavior'
miniloader/lualib/miniloader.lua:156: in function <miniloader/lualib/miniloader.lua:137>
(...tail calls...)
miniloader/control.lua:135: in function 'handler'
miniloader/lualib/event.lua:15: in function <miniloader/lualib/event.lua:13>

And even when blueprint is used :/