I figured I'd be able to answer all of those questions pretty easily. The texture thing I'm not sure about, but if your card doesn't support something that large then there may be major issues with downsampling on a per-instance basis (I'll bet the game stores it full-size and downsamples when feeding it to the videocard, which in your case may be happening every frame). This should actually probably be treated as a bug if it hurts performance that drastically, though I'm no expert on that. I don't know what to tell you about the Herc 2; I'd say remove it until I have time to fix it if I didn't know that everyone would then post errors about it being missing. The Faustus though I can definitely fix. I believe I actually know why we're getting those stupid errors, so I should probably take another look at the Leviafenris too and see if there isn't a pattern. Am I correct in assuming that it doesn't happen with the retail model?
As for the glowmap, this is my take on it: the old map is useless, as no one in their right mind would use adveffects without mv_models and mv_models disables the glow. So you can get rid of an ani and the eff, and the error dissapears. Yes, it could be fixed, and I asked Turambar to do an animated glow when he redid the maps (he hasn't yet). No, it's not as simple as shifting things around a bit, but it should be close. I could probably do it if I had the original photoshop file for the glowmaps and had a large enough amount of time to hammer away at it, but 2d art is not my specialty. But as of right now, it would be easier to base an animated map off of the static glow than to rework the ani to fit the new lines so there's no reason to keep the old animated map around as far as I can see.
