Update coming! Brave testers needed!

[Patrik]

I am playing through the main story now. However, all of the monsters are curiously missing. I just went into the water-logged level, and didn't see the invisible stalkers whatsoever. Nor, did I see any others when I got to the area where I have to create the explosive.

I installed both the file you uploaded and the optional files from A Machine For Pigs.

I appreciate you going through the game again.

Like Pluto said, the monsters were of course there when I tested it, but you never know. It's quite possible something that works on my computer doesn't work for someone else.

First thing to do is to make a clean install, install the update carefully following the instructions in the first post, don't copy the AMFP files, and test the game again.
Let me know if the problem persists.

If this fixes the issue, then you can copy the pig files over, but do so carefully and follow the instructions in the first post.