Hi, I am having pretty much the same issue, except the file is different:
This file contains invalid data. (error 11FD)
I am running a Windows 7 64x OS
I am also trying to install on a steam copy, with the game properly prepped (no updates, community off, first run complete, no UAC)
I have attempted a download from a different source and reinstall of the game but get the same error.
Haven't found any solutions elsewhere either.
Edit: Hey, I seem to have found a way to get it working (though it is a bit odd). I installed the Camarilla 1.4 mod first, which worked fine. Then I installed Final Nights overwriting it. Now, I wouldn't say this is a good fix, but it seems to have provided the right files for Final Nights. I have been able to play through Santa Monica just fine so far! Loving Clan Salubri!