Hi, I found a bug with your engineers workshop, it involves the crafting upgrade. It allows the pre craft materials and the post craft item to both pop.

1. Place workshop, right click it.
2. Put a crafting upgrade in the modules
3. Switch back to main and use the crafting spot to make something
4. ESC out of the GUI once a recipe is entered
5. You'll notice when holding shift with WAILA type mods the inventory of the workshop has both the materials we entered AND the finished item.
6. Break workshop with pickaxe, both precraft and post craft items drop. Basically duping your crafting materials.

FIXED.