Hello and I got a crash report right here: https://pastebin.com/tiFG7Yf4

This is the recipe file I currently have: https://pastebin.com/3WRSi1hD.

I am not sure what is wrong but I used only the input item slot and the output energy slot.

I've been receiving this error as well while trying to create a boiler multiblock using "any:fuel". Setting the input fuel to specific items doesn't cause this crash error, but ONLY when using "any:fuel".

EDIT: I've also tested a recipe using item fuels using zenscript. I did remove the similar json recipe so it wouldn't interfere with the zenscript recipe and I got the exact same error. So it's definitely an error using item fuels as input.

Below is a test script using vanilla items/fluids, because I hadn't added steam yet.

import mods.modularmachinery.RecipeBuilder;
import mods.modularmachinery.RecipePrimer;

val steamboiler = mods.modularmachinery.RecipeBuilder.newBuilder("steam_generator_zs","boiler_iron",1,0);
	steamboiler.addFuelItemInput(16);
	steamboiler.addFluidInput(<liquid:water>*1);
	steamboiler.addFluidOutput(<liquid:lava>*1);
	steamboiler.build();

I tested with others and they don't crash.

I found out that "any:fuel" causes the game to crash.