Cross-posting this bug report in the Factory Planner mod because the stack indicates a missing field: https://github.com/ClaudeMetz/FactoryPlanner/issues/249

With the Factory Planner open, immediately after clicking on one of the steam ingredients in the Factory Planner GUI to add a recipe, the following crash occurs:

The mod Factory Planner (1.1.78) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event factoryplanner::Custom event (ID 282)
__factoryplanner__/backend/data/Machine.lua:62: attempt to index field '?' (a nil value)
stack traceback:
    __factoryplanner__/backend/data/Machine.lua:62: in function 'normalize_fuel'
    __factoryplanner__/backend/data/Line.lua:100: in function 'change_machine_to_proto'
    __factoryplanner__/backend/data/Line.lua:151: in function 'change_machine_to_default'
    __factoryplanner__/ui/dialogs/recipe_dialog.lua:94: in function 'attempt_adding_line'
    __factoryplanner__/ui/dialogs/recipe_dialog.lua:258: in function 'early_abort'
    __factoryplanner__/ui/base/modal_dialog.lua:154: in function 'enter'
    __factoryplanner__/ui/event_handler.lua:209: in function <__factoryplanner__/ui/event_handler.lua:189>
    [C]: in function 'raise_event'
    __factoryplanner__/util/raise.lua:20: in function 'open_dialog'
    __factoryplanner__/ui/main/item_boxes.lua:11: in function 'add_recipe'
    __factoryplanner__/ui/main/item_boxes.lua:161: in function 'handler'
    __factoryplanner__/ui/event_handler.lua:157: in function <__factoryplanner__/ui/event_handler.lua:114>
stack traceback:
    [C]: in function 'raise_event'
    __factoryplanner__/util/raise.lua:20: in function 'open_dialog'
    __factoryplanner__/ui/main/item_boxes.lua:11: in function 'add_recipe'
    __factoryplanner__/ui/main/item_boxes.lua:161: in function 'handler'
    __factoryplanner__/ui/event_handler.lua:157: in function <__factoryplanner__/ui/event_handler.lua:114>

I've only been able to produce this crash when clicking on steam - all other ingredients/recipes have been fine so far.

Reproduction

1. Load save
2. Open Factory Planner
3. Click on steam ingredient in upper right corner.

Factorio log: https://github.com/ClaudeMetz/FactoryPlanner/files/13998917/factorio-current.log
Save here: https://github.com/ClaudeMetz/FactoryPlanner/files/13998926/Ultracube.zip

Sorry, I'm not sure what you mean by "the stack indicates a missing field". The recipes involving steam aren't particularly abnormal, and are accepted by the game, and it looks pretty clearly like an issue with Factory planner logic to me.

I also had this crash - Factory Planner is choosing the "wrong" boiler by default (the vanilla one which isn't enabled) and this ends up crashing somehow. If you go into the Factory Planner preferences and set the default boiler to be the Ultracube one then it works. Factory Planner doesn't deal very well with how steam temperatures are handled in the Ultracube recipes though - it treats "steam, any temperature" (input to various recipes) and "steam at a specific temperature" (output of various recipes) as distinct fluids and won't match them up in all cases.

I didn't think to look in the preferences. Switching the default from the vanilla boiler to Ultracube's eliminated the crash for me too. Thanks!