I recently bought the wonderfully looking and reviewed Amnesia The Dark Descent and I'm trying to install it.

The first time I tried to download it, I had to stop in the middle of the download (may have broken something).

The second time I tried to download, at the end of the download it gave me the following error:

Failed to fetch https://private-ppa.launchpad.net/commercial-ppa-uploaders/amnesia/ubuntu/pool/main/a/amnesia/amnesia_1.2.1-0ubuntu2_i386.deb Size mismatch

Now, whenever I try to download it, it gives me this error:

The following packages have unmet dependencies:

amnesia: Depends: libalut0 (>= 1.0.1) but it is not going to be installed
         Depends: libc6 (>= 2.4) but 2.15-0ubuntu10.3 is to be installed
         Depends: libfontconfig1 (>= 2.8.0) but 2.8.0-3ubuntu9.1 is to be installed
         Depends: libfreetype6 (>= 2.2.1) but 2.4.8-1ubuntu2 is to be installed
         Depends: libgcc1 (>= 1:4.1.1) but 1:4.6.3-1ubuntu5 is to be installed
         Depends: libopenal1 (>= 1:1.13) but 1:1.13-4ubuntu3 is to be installed
         Depends: libsdl1.2debian (>= 1.2.10-1) but 1.2.14-6.4ubuntu3 is to be installed
         Depends: libstdc++6 (>= 4.1.1) but 4.6.3-1ubuntu5 is to be installed
         Depends: libxft2 (> 2.1.1) but 2.2.0-3ubuntu2 is to be installed
         Depends: zlib1g (>= 1:1.1.4) but 1:1.2.3.4.dfsg-3ubuntu4 is to be installed

I already searched the net and ran a few command line commands. Ex:

sudo dpkg --configure -a  
sudo apt-get install -f

Or configure the software packages to download from Main instead of the local UK server. But I'm really not figuring out a solution.

I have a fresh install of the latest LTS (12.04). The only non-standard thing so far is that I installed gnome-shell (?) because I really can't stand Unity.

Help would be much appreciated. I am currently more than entertained enough with World of Goo and Command & Conquer, but I will want to play Amnesia in the close future.