No, no materializing weapons (unless she has an item box that the GM didn't mention), I'm just confirming that if she gets the right materials and equipment together, she can craft firearms and explosives.

I don't expect her to find rifled barrels tucked away in some forgotten corner of the lair. She's gotta get them crafted by a master craftsman. 

Unless these tunnels are all lit up, does she possess as a goblin some sort of darkvision where she can see only so many feet in front of her as if it was dim and grayscale?