Ok.

I got multiple users on that computer, maybe it's the problem ?

There's the admin, and I got my own name as a user with limited rights (asking for password when installing apps). I got the password by the way.

I tried changing permissions of the MoI app and it's sub-directories with no success.

Will tell you how it goes with 10.8 :)

Installed 2.52 + 10.8.2 and everything is fine ! Yay

Hi DesuDeus, that's great news! It is still a mystery to me why it was not working on your previous machine... Probably something related to permissions but it's hard to know exactly what.

- Michael