I just want to make a nif model unaffected by lighting, so that it is bright even in dark areas. I'd rather not use a glow map if possible, as that would increase my texture ram needed. I tried using a glow map and couldn't get it to work.

Is there just a setting on the nif to make it full bright?

You don't need a glow map. A glow map is only a mask applied to the emissive color of the model to make certain parts glow and other parts not. That's why a glow map doesn't work with the emissive color set to black (which is most likely the reason why your glow maps didn't work). If you want the whole model to glow you can simply set the emissive color in the material property of the nif, no need for an additional texture.

EDIT: Emissive color doesn't show up in the CS afaik, it only shows up in Nifskope and in game.

Well that seems to work, but it appears very shiny now, or the hdr glow on it is pretty intense. Any way to cut that off?

Darken the alpha channel of the normal map ! - it controls the light reflectivity of the object so darkening it will make the object reflect less light.

Yes, but here object does not reflect the light - but the light emits from it instead, so it isn't affected by the alpha channel of normal map. The thing that can control strength of emissive properties of texture is the glow map.

The alpha channel of the normal map is already pure black. I don't have a glow map, and I've never been able to get them to work, there must be a setting in the nif to make it use one? Would I make it pure black to make the texture look bright but not glow or have HDR?

Like I wrote above, a glow map is a mask that is applied to the emissive color. Without glow map the whole mesh will be affected by the emissive color. If you want less glow simply adjust the emissive color. Can be anything from solid black to pure white - in your case something inbetween would work best, like red, green and blue @ 0.5 for example. You can even use a color if you want, like yellow or red or whatever. But in most cases the texture should be enough for adding color.

A glow map is only necessary if you want certain parts to glow and others not. Or if you want certain parts to glow stronger than others. Can be seen on the Daedric equipment for example - the red parts glow, but the rest of the mesh doesn't. Since splitting up the mesh into red parts and other parts is not an option (the red parts are only part of the texture and not part of the geometry after all) a glow map is needed.

I can only add to Phitt's info that most of the time glow map doesn't have to be as detailed as color or normal map itself. It is usually saved as grey scale dds with DXT1 compression and no alpha channel info. And its size can be half or even lower than that of color map so it won't be increasing texture memory much.