Opening TF2 wont do it, you actually need to join a game to get the config to write. Either way apparently the guy didn't have steam sync set to automatic or something and he left the chat before telling us whether it actually worked so presumably it did, otherwise he'd have come back already.
Hammer crashes a lot, I suggest you try again, keep working at it for an hour to let it properly place its files, set preferences, etc. Its quite an unstable program, but easy to use once you actually start using it.
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