It looks like the demo release was a moderate success.
For those of you who do not have Doom 3 installed, I have released a youtube gameplay video of an earlier version of Zombie Slayer (only difference is in the credits sequence). You can view that here: Youtube.com (WARNING: This contains SPOILERS).
At this time, I am not looking for any help with the mod. Thank you for your interest.
Please keep checking back with the moddb Slayer page. I will be continuously uploading images from further chapters of Zombie Slayer.