Hmm, I downloaded the Mega ISO myself, to try it. It seems to be a different filesize to my IMG/CUE file, but that shouldn't make a difference, really... Admittedly, I downloaded my version of TnC from a different website in multiple parts and pieced it together...
But, for whatever reason, your installer program isn't installing the game fully... Or something... What ISO Mounting program are you using, just in case?
Well, most of the file-size differences may not be important... (Though the english script and 0cg.pak seem way off).
Let's see... Looks like you're using Windows Vista to play the game. Luckily I still have my Vista laptop. I'm going to go give it a try, myself.
-- Edit: Hahah, wow. That was a chore to try and get it working... Couldn't get Daemon Tools Lite to install at all, had to find a bunch of different EXE's for that. Then installed TnC, and now it won't recognize the mounted ISO. Gonna try VirtualClone Drive now...
Have you tried running the game WITHOUT the English patch, first? Like, delete/remove/uninstall TnC first, and then after re-installing try running the game BEFORE running the patch?