As the title says when you disable the chemical recipies then the game won't load because it contains duplicate items. To be precise Steel Plates exists 2 or more times.

Thanks for reporting. I am surprised this issue must have existed for a very long time...
Should be fixed in 0.17.7 / 0.18.9 / 1.0.2 / 1.1.2.

Glad I could help. My guess is people didn't normally turn of the chemical recipies. Or were to lazy to report it. Still thanks for acting on this so fast.

Yes, I also guess so.
The vanilla poison capsule uses coal and steel plates as main ingredients for "poison", not sensible at all.
That was why I provided chemical recipes... (But as always, whenever vanilla values are changed, I provide options so users can still stick to vanilla.)