Currently, fuel slots of custom containers can only use custom fuel registries. It would be nice if users could also use the vanilla fuel registry (coal, wood, ...).

Until I implement this, users can use the following work-around if they want to use the vanilla fuel registry:

1. Download Quarlies template pack from https://github.com/knokko/knokko.github.io/raw/master/resourcedumps/template_1.17.cisb
2. Put it in the Custom Item Sets folder
3. Use the Combine item sets feature of the Editor to combine the template pack with your own item set. Use your own item set as primary pack
4. Use the Vanilla Fuel custom fuel registry as fuel registry for a custom slot
5. Optional: delete the placeholder item (this is also part of the template pack, and you may or may not want to have this)
6. Optional: delete the template container (this is also part of the template pack)