From the patch notes:
- Replaced ItemPrototype::fuel_category with ItemPrototype::fuel_categories.
Ashland tree seeds use the old 'fuel_category' designation, so the mod won't load in Factorio version 2.1.20 or later.
Just a heads-up for you.
There's a secondary hurdle after that that I don't really understand, but I fixed it on my end by removing their fuel statistic entirely. Good luck! 😀
