There seems to be some mix ups between the full game and the demo here. In post 2, Menahune is talking about the full game, while Rushes is quoting a discussion about the demo from another post.
With the demo, some users ended up with a file without an extension name (i.e. "exe") in their install folder. I have no explanation for this, other than it probably was some quirk at the server where it was stored. I've tried to fix the problem by uploading to a new server.
Obviously, some players have problems installing the on line version of the game from The Adventure Shop. I'm not an Adventure Shop costumer, and don't know how they've chosen to distribute the game files. But if someone has problems after trying the methods described in MaG's and Kjos' posts above this, feel free to contact me, and I guarantee that we can solve it somehow.