ToME: the Tales of Maj'Eyal

I changed my password to my tome account and the game logged me out accordingly.

I've been playing before the release on Steam but purchased the game & DLC through Steam. Now that I'm logged out, the only login option is Login with Steam, which insists on a new registration and won't let me login with my old account because it's already taken. By me.

Feature, bug, or an obvious workaround I'm missing?

I just registered right now in the forum for the same problem

Have you logged in to te4.org and linked your steam account with your te4 profile?

I did link it, but it did not let me log in as my old name.

Now I have made a new account linked to my Steam, and tried to go into it and change the name to my old name, and that does not work, either.

Apparently there is no way to link a pre-Steam account to a Steam copy of the game.

I'm sure there is, as that is what I did.
Did you log on to ter.org with your old account, or your steam one?

My account is over 5 years old and is not linked to my Steam account (I bought the game + DLCs through steam). The following worked for me:

1) Download the stand-alone version of game
2) Launch the stand-alone game and log in to your old account
3) Exit the game
4) Launch the stand-alone game again to confirm your account info was saved and logged in
5) Launch the Steam version and you should automatically be logged in via your ToME account

If it's possible to unlink your Steam account from your ToME account, you might want to do that before trying the above.

I logged onto te4 with my old account and pressed the link to Steam account button. I then performed the relevant steps, but the linking did not occur. I then made a new account via Steam, hoping I could resolve the issue having done so, and now I'm not sure how to remove the Steam account.

Mine had been linked fine to my old te4 account previously, but I needed to reset the password and that's when the trouble started, as it logged me out of my old account and there wasn't a way to log back in. Will try magelike's workaround.