The mod Construction Drones (0.4.9) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event Construction_Drones::on_ai_command_completed (ID 113)
The mod Transport Drones (0.3.3) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event Transport_Drones::on_robot_built_tile (ID 47)
Transport_Drones/script/proxy_tile.lua:56: attempt to call local 'remove_function' (a nil value)
stack traceback:
Transport_Drones/script/proxy_tile.lua:56: in function 'road_tile_built'
Transport_Drones/script/proxy_tile.lua:113: in function 'handler'
core/lualib/event_handler.lua:44: in function <core/lualib/event_handler.lua:42>
stack traceback:
Construction_Drones/script/construction_drone.lua:2102: in function <Construction_Drones/script/construction_drone.lua:2047>
(...tail calls...)
core/lualib/event_handler.lua:44: in function <core/lualib/event_handler.lua:42>
stack traceback:
[C]: in function 'raise_event'
Construction_Drones/script/construction_drone.lua:2102: in function <Construction_Drones/script/construction_drone.lua:2047>
(...tail calls...)
core/lualib/event_handler.lua:44: in function <core/lualib/event_handler.lua:42>