According to the wiki, you need to have either 100 metalworking, or 100 sculpting to become a Tinkerer. When I tried to pick up this school, the NPC Versanto says "congratulations you're now a Tinkerer", etc BUT it does not change my class to Tinkerer, and when I try to scribe the beginner formulas he gives, it says I have to have 100 sculpting to join this school, even though my metalworking is 200.
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