FMF - 1.0.6

: 101.286 Error MainLoop.cpp:1195: Exception at tick 21509070: The mod Fluid Must Flow caused a non-recoverable error.
: Please report this error to the mod author.
:
: Error while running event FluidMustFlow::on_built_entity (ID 6)
: FluidMustFlow/linver-lib/entity-utils.lua:21: attempt to index local 'neighbour' (a userdata value)
: stack traceback:
: #011__FluidMustFlow__/linver-lib/entity-utils.lua:21: in function 'getConnectedNeighbours'
: #011__FluidMustFlow__/control.lua:68: in function 'ductConnectionsControlEvent'
: #011__FluidMustFlow__/control.lua:427: in function <FluidMustFlow/control.lua:422>
: 101.286 Error ServerMultiplayerManager.cpp:92: MultiplayerManager failed: "The mod Fluid Must Flow caused a non-recoverable error.
: Please report this error to the mod author.
:
: Error while running event FluidMustFlow::on_built_entity (ID 6)
: FluidMustFlow/linver-lib/entity-utils.lua:21: attempt to index local 'neighbour' (a userdata value)
: stack traceback:
: #011__FluidMustFlow__/linver-lib/entity-utils.lua:21: in function 'getConnectedNeighbours'
: #011__FluidMustFlow__/control.lua:68: in function 'ductConnectionsControlEvent'
: #011__FluidMustFlow__/control.lua:427: in function <FluidMustFlow/control.lua:422>"
: 101.286 Info ServerMultiplayerManager.cpp:776: updateTick(21509070) changing state from(InGame) to(Failed)

placing an oil burning heat source triggered a game crash from FMF. Interestingly enough, there are no ducts connected to the oil burning heat sources.

Thank u for ur report. Can u give me the name of what bob mod add the oil burner?

Should be Bob's Power (https://mods.factorio.com/mod/bobpower)

Bob's burner heat source, which also uses a neighbour bonus, does not trigger a crash, nor does Bob's steam assembling machines

Should be fixed

Still appears broken in FMF 1.0.8

:  280.777 Error MainLoop.cpp:1195: Exception at tick 21899812: The mod Fluid Must Flow caused a non-recoverable error.
: Please report this error to the mod author.
: 
: Error while running event FluidMustFlow::on_built_entity (ID 6)
: __FluidMustFlow__/linver-lib/entity-utils.lua:18: attempt to index local 'neighbour' (a userdata value)
: stack traceback:
: #011__FluidMustFlow__/linver-lib/entity-utils.lua:18: in function 'getConnectedNeighbours'
: #011__FluidMustFlow__/control.lua:68: in function 'ductConnectionsControlEvent'
: #011__FluidMustFlow__/control.lua:427: in function <__FluidMustFlow__/control.lua:422>
:  280.777 Error ServerMultiplayerManager.cpp:92: MultiplayerManager failed: "The mod Fluid Must Flow caused a non-recoverable error.
: Please report this error to the mod author.
: 
: Error while running event FluidMustFlow::on_built_entity (ID 6)
: __FluidMustFlow__/linver-lib/entity-utils.lua:18: attempt to index local 'neighbour' (a userdata value)
: stack traceback:
: #011__FluidMustFlow__/linver-lib/entity-utils.lua:18: in function 'getConnectedNeighbours'
: #011__FluidMustFlow__/control.lua:68: in function 'ductConnectionsControlEvent'
: #011__FluidMustFlow__/control.lua:427: in function <__FluidMustFlow__/control.lua:422>"
:  280.777 Info ServerMultiplayerManager.cpp:776: updateTick(21899812) changing state from(InGame) to(Failed)

Can u give me ur savegame? I'm unable to reproduce this error

factorio 0.17.79
https://drive.google.com/open?id=1IQI46R6S-AuVB6jYuBw90pHMy3uDTDuS

a newly generated test map with only bobs power and FMF activated. I was able to confirm the crash in singleplayer and confirm the crash in the above save file

Should be fixed in 1.1.0

Fix confirmed in FMF 1.1.0 and Factorio 0.17.79!

no crash in testmap provided - pass
no crash in multi-mod map - pass

Thank you for the fix