Custom 'faces' on grunts

[Hailfiretank]

Firstly, hello

Ok, I'm sure you've played the 'Dark Room' custom story. Now, during this story, the enemies had custom 'faces' - ie. the grunt had a trollface.

I am aiming to do a similar thing to monsters in my custom story, however I am having a bit of trouble:

I have done some searching around for help for this, and I know that to create a custom monster, you need to create a billboard image for it (aka an image file (in my case .png) and a .mat file). Now, this is where a bit of trouble appears:

In the model editor (I used the material editor to create the billboard - I used the same terms as DracoStriker and Danarogos used for their trollface billboard), every billboard spawns upside down. Now, if they spawn upside down in that, are they the correct way up in the Level Editor (I tried rotating my billboard vertically, but it stayed upside down in Level Editor).

Secondly, I spawned my custom monster (It had an upside down billboard on it) in the Level Editor. I then loaded the map up in Amnesia. The monster was there, however he didn't have a billboard - it was just a normal grunt.

So, to put it simply, the problems:
1. What settings should I set it at in the material editor, to make it a 2d billboard that 'sit's on the grunt's face?
2. To make the billboard appear the correct way up in game, should I leave it upside down in the model editor?
3. How do I prevent the monster from spawning without the custom billboard in game, even when it has the billboard in the level editor?

I have checked the forum and wiki, but I cannot find answers to any of these trivial questions :/

Thanks to anyone who can help, and sorry if you've already been asked these questions.