About Omnilights

I'm currently working on a model, which I would like to have a constant fiery red glow around him.

I know how to make an omnilight, but where would I place it to get this effect?

And what do the parameters mean? (Attenuation, Multiplier, Decay etc..)

Max 5 and Art Tools as always. Any advice would be appreciated.

You should place it in the center of the model. Since wc3 can't calculate cast shadows the light will pass right through the mesh.
You don't have to worry about attenuation and decay for wc3, just the color and the intensity multiplier which by the way as far as I realized the limit for wc3 is 2 (as far as I can remember). Any value above that will have the same intensity as 2 in-game.

That's all I need to edit?

yes, that's all
also make sure that shadows are turned off, though they should be by default.

Damn, it didn't seem to work in game.

I had the multiplier at 2, and the color an orange yellowish color. And shadows weren't turned on.

Omnilights don't seem to work too well, i attempted to make a form of night-combat style map by removing the normal evironment lights and giving units torches on their back which shed light around them, but i noticed that the lights would randomly stop working for no ovbious reason.

Strange, every omni I exported works fine. I even exported single omni lights, with no mesh whatsoever, and they worked fine.

Why don't you become a teacher TDR. :) As soon as the students gets used to your hurtful critisizm they will love you.

I didn't have any trouble with the lights themselves as models, i think the models must have become corrupted while i was saving the map. I noticed tha when i first imported the first torch model, it worked fine. I then proceeded to import a bunch of different torch models for each different soldier model so it fit right and i noticed that some of the earlier torch models stopped working (i added them one by one as i worked, so a total of about 20 models were added over the period of about 10 days.) When i re-imported the older torch models they proceeded to work fine, but other lights promptly started failing. The models appeared perfectly normal, but the light part didn't appear at all.

Also, for some odd reason i encountered squares of terrain which refused to be affected by the omnilights.

aye, me too. it seems to be some strange engine bug.

I believe it happens with too many light sources. It's happened to me a few times from placing too many torches in an area.