Where? Is it when she cries out in pain after the Grendelkin breaks her arm and is then defenseless for the rest of that story? Or is it when she's clearly in too much pain to do much when her guts are hanging out?
When she's actually fighting? Yeah, she can feel it, but it doesn't seem to actually impair her.
Damage impairs her (like an inability to use a broken arm effectively), but pain? Not so much. Again, see Even Hand for examples.
I haven't, so fair enough. I posit, though, that the axe in Heorot was not the same axe as the one in Even Hand, since she loses that first axe.
Very possible. I'm...not sure how this is a criticism (given it's a current, ie: post-Heorot build), but very possible.
I don't think she knew at all that it was immune--you'd think during that whole information session thing before the fight, she might have mentioned that to Harry.
Immune to her magic and immune to Harry's are different things, she could easily know the first but assume it had to do with them being related and not realize it'd apply to Harry as well.
Also, why does Harry then speculate that the axe, as an enchanted and runic weapon, is specifically what the Grendelkin's catch might be? She wounds it so it's clearly bleeding--meaning that she must have done a solid 14 shifts of damage if it wasn't a catch to it. So either she rolled as high as she possibly could while the Grendelkin rolled low, or it did indeed have an effect on its own Toughness power. And, again, the axe used there was not the same axe as in Even Hand.
The axe might easily be it's Catch. That doesn't mean it's mechanically magical or an Enchanted Item, though, just that she prepped it properly to be the Grendelkin's Catch.
They recover that quickly after treatment. Remember that Harry first finds her while she's still treating herself, and getting her out of the house only aggravates her injury--she probably didn't start healing at all until she got to the Carpenters and had her wound sealed up. By the next day or so, she's on her feet. Remember that a "scene" is a fluid thing--it could mean an hour, but it could also mean the next day.
Uh...Inhuman or better Recovery definitionally needs no such treatment to begin healing, which throws all that out the damn window, timeline-wise. But maybe I'll throw that in as her Catch and up her back to Supernatural. That would make some sense, I suppose...
Where are you getting this from? We don't really see anything regenerating right in the middle of a fight like that, short of the Uber Ghouls, which are noted as being an exception for being able to do that, and the White King, who's also supposed to be somewhat above and beyond normal.
We see Ghouls do it occasionally (on the rare occasions Harry doesn't kill them outright, see the boat fight in White Night for examples)...and they're the only Supernatural Recovery baddies we run into regularly. Which is the same level of Recovery the White King is listed with, btw.
Again, we only ever see Gard get wounded in such ways that she needs some kind of outside treatment--a broken arm with the bone sticking out, and her intestines spilling out, neither of which can really just regenerate.
Which is why I'm considering adding that as her Catch, since, by the rules, no level of Recovery power needs that kind of thing.
I suggest you take another look at the Sponsored Magic list. I helped to write the current version of Rune Magic, which is still -4 and does account for the lack of Evocation.
I don't use homebrew stuff (other than relatively minimal amounts of my own) in this thread. Simpler and more generally usable that way, I think.