Amnesia Custom Story Installer

[MulleDK19]

I'm trying to use the installer, but I get an error message that says that Amnesia isn't installed on my computer. I see that someone has had that problem before me, but that it was fixed in the last update.
Do you have any idea of what could've done it?

What version do you have? Retail or Steam?

How did you install it?

I have the Steam version. And do you mean how I installed Amnesia or how I installed the installer?

Installed Amnesia.

Which OS are you using? And is it 32bit or 64bit?
Did you download the game through steam, or copy it from another folder?

I downloaded it through Steam. Also, how do I chech my OS? Sorry, I'm not that good at computer-related stuff.

What version of Windows do you use? XP? Vista? 7?