How long does it last when it changes to 1? I don't know anything about global variables. Will it be able to work with effects that will last four in-game hours?
It will stay 1 for several hours; I'm thinking to make it reset to 0 right before every lunch and dinner.
You need to build a script that starts when it detects that the NoM_lactose variable is 1. After that, you can pretty much forget about the variable, because it's only a condition to start your script.
Speaking of the progress, while I search for new glass textures, I worked on the campfire a bit and added a skewer to it. In the new NoM version you'll be able to roast meat and fishes without a grill (although the grilled versions will give you more benefits) and so I had to adapt the campfire model.
Here it is in a http://i794.photobucket.com/albums/yy227/_Taddeus_/NOM/CampfireNifskope.jpg?t=1275988049 and in a http://i794.photobucket.com/albums/yy227/_Taddeus_/NOM/Campfire.jpg?t=1275988021.
As you may notice, in that second shot I set up the campfire very close to Thirsk. This would not be possible in the current (2.13) version of NoM, because there are control scripts to avoid that the player can set up a camp in a town or in a building. These controls are still present, but I made them much more accurate using an original idea by Toccatta from the old NoM threads and modifying it here and there. Basically, in the current version, the game prohibits you from placing a campfire in cells which have a certain name. So if you are in the cell "Thirsk", you can't build a camp even if you are very far from the buildings. In the new version, this check is no more based on cell names, but on the distance from a square activator hidden underground. This allows to follow the town borders with a certain accuracy and will avoid problems when one's far away from the buildings.
In these screenshots you can see what I did:
http://i794.photobucket.com/albums/yy227/_Taddeus_/NOM/IllegalGnisis.jpg?t=1275988150
http://i794.photobucket.com/albums/yy227/_Taddeus_/NOM/IllegalCaldera.jpg?t=1275988152
http://i794.photobucket.com/albums/yy227/_Taddeus_/NOM/IllegalAhemmusa.jpg?t=1275988155
http://i794.photobucket.com/albums/yy227/_Taddeus_/NOM/IllegalMolagMar.jpg?t=1275988157
http://i794.photobucket.com/albums/yy227/_Taddeus_/NOM/IllegalMaarGan.jpg?t=1275988160
http://i794.photobucket.com/albums/yy227/_Taddeus_/NOM/IllegalSadrith.jpg?t=1275988181
In the area in the squares it's illegal to build a fire or set up a bedroll. You won't see them in game because I dragged them underground after taking those shots, but they'll be there to check.
The best part is that the square activator can be easily used by anyone to add this feature to new mods, while in the 2.13 version this is not possible. Just drag it to the game world in the CS, resize it if needed, and all the area within will be off-limits to camping.