[Vicious Love]

Best of luck. I spent a few days working on a skaven mod, and ran into a mostly figurative brick wall the moment I got past the bare essentials.
That is to say, all the stats and flavor text are in place, and I know someone who could whip up some reasonable quality sprites, but all the skaven game mechanics not represented by Dom 2 unit stats seem impossible to mod in at the moment.

I've been experimenting with the "standard" ability to simulate skaven pack morale, and have gotten what you might call mixed results.

There's presently no way to make a weapon have an increased chance of causing battle afflictions.

Disease causing attacks(Rather than disease clouds), gouts of warpfire, poison wind globes and poisoned weapons can presently only be made by modifying existing weapons, which is an awfully unsanitary way of doing this sort of thing. If only there were a #duplicate [number] command, to make a new weapon identical to an existing one, but with a different serial number.

A supply penalty and generous pillage bonus seem to semiadequately portray skaven logistics, but the ability to substitute unburied corpses for supplies would be ideal. Plus, since there's no way to tag a unit "starves first, eats Last", I had to make skavenslaves #neednoteat and #noheal, to keep them from eating all the Clanrats' food.

There's presently no way to start plague monks/skavenslaves/etc. off with battle afflictions, Ikit Claw cannot start out horror marked, and so on.

Clan Pestilens troops cannot be made immune to Miasma, not can they be given any noncombat disease-related abilities, nor can the Council Bell Tower site, Screaming Bell unit and Horned Rat pretender increase turmoil and misfortune, Lord Skrolk increase death, and so on.

Reinvigoration, particularly reinvigoration penalties(For Pestilens troops) can't be modded in, nor can partial Quickness(For Pestilens troops and assassins), Air Shield(For Snikch), Blood Vengeance(For Thanquol), Luck(For Queek and Thanquol), siege bonus(For sappers and Warlock Engineers), patrol bonus(For Quartermasters, the professional logistics bastards and Brute Squad leaders of the Underempire) and much, much more.

Gray Seers can't be given Screaming Bells, experienced Gutter Runners can't be upgraded to Assassins, Eshin contracts can't expire after one assassination(Gladiator style).

Summoning Vermin Lords can't incur the risk of a horror mark(Which is a shame, since this could be a nice overlap between Earthdawn/Dominions/Warhammer. Skaven summoning is based almost entirely on overkill. Hurl all you've got at reality, until it breaks).

Screaming bells can't curse(Ark style), can't be mobile, juggernaut style temple checks, and can't disrupt magic, nor can the Doomwheel.

For that matter, not a single aspect of the Doomwheel can be simulated.

Warpstone consumption can't be simulated, neither as a battlefield spell nor as an insanely risky, mostly random, low death-gem cost alternative to empowerment.

Skaven can't be made inherently unnatural, random sorcery picks and truly random spell picks can both result in the nature path, and empowerment cannot be made to cost more nature gems/be impossible.

Cross breeding can be modified to not require the nature path, but this affects all nations, not just Clan Moulder. Moulder Warlocks can't be given a bonus to this spell, either. Entirely new spells such as Death Frenzy are entirely out of the question.

Gray Seers can't be made to appear of their own accord, hero style, when your Dominion is high enough and you've got relatively few Seers.

And that's just what I could think of offhand. I've actually got a few handwritten pages of planned features, which I go into in great detail, most of which have more to do with my take on the skaven and the transition from tactical to strategic than with copying and pasting Warhammer stats. None of the aforementioned features are even remotely feasible. Still, even without expanding on the material already present in Warhammer, I imagine a comprehensive Warhammer mod would be much, much more demanding than a skaven mod and, if these are just some of the problems I've run into after about two days of planning and two days of work/testing/finding roundabout solutions to problems, I really don't envy you.
This is all too bad, because my conception of the Skaven seems to have an ideal strategic and tactical niche in Dominions 2. I figure they'd replace Pangaea, as some of the two nations' abilities are rather similar, and Pangaea isn't needed to keep another specific nation in check. Besides, Ulm has to be there to get its *** kicked by Skavenblight, Ermor has to be there to pwn the Underempire, and Marignon has to be there to pwn Ermor.
Ack, I'm getting way ahead of myself, it'll be a long, long while before I can get anything remotely playable done. And yet I've already got three themes in mind, each of which almost completely redefines Skavendom. My favorite is Dharmic Hordes.

What? Quit staring at me. Not like I'm the first person to make plans he's got no chance of actually carrying out.