I finished Portal 2 and now I'm doing the achievements. How do I return to the place in which you get the "You Made Your Point" achievement? I tried with the dev console and it gets me to the right level, but I can't get the achievements. Are they like one-time-only achievements?
sv_cheats via the dev console immediately disables achievements.1 Try save/loading or restarting the game after disabling
sv_cheats before attempting the achievement. You'll also want to use
map instead of
changelevel, or achievements will be nullified.2
Re-loading Chapter 8 from "New Game" is another option, but the dev console is more adventurous.