The auth code is what the game gives you and what you submit here. The save code is what this site issues in return, and it is what loads your progress back into the game. The map loads only save codes issued here, so typing an auth code into the game will not work.

A code is tied to the StarCraft name it was saved under, so it only validates for the account whose ID matches that name. If you picked the wrong ID when you signed up, go to your dashboard, delete the account, then sign in again and choose the right one.

Auth codes from a modified map, or from an older version of the map, are never registered. Download the current official map above, run it, save, and submit the new auth code it gives you.