Here is the full list of all 12 Blackwell Convergence achievements. It takes around 2-3 hours to unlock all of the achievements on Windows.
Find the secret extras menu
Finish the game at least once
Defeat the Countess with one throw of an improvised lasso
Save Charlie Meltzer's life
Have a few drinks, but you might regret it in the morning
Give Allen some hope before he goes
Keep a clear head, but others might think less of you
Distract the cat only once
While holding Frank's script, get though a performance without flubbing a single line
Convince Frank that you are an artist on your first try
Finish the game without asking Joey for a single hint
Finish the game in commentary mode, from the opening menu till the end