I decided to look at the mod myself, even though I'm totally bad at this. I opened the mod in the CK. Since it's a resistance message, which is a spell thing, I decided to look up the magic effect entries for the knife throwing script. There's a script on all of them called "KnivesDamage." I tried to look at the script's properties and it threw an error at me:
"SCRIPTS: Cannot open store for class "KnivesDamage", missing file?"
It might just be doing that because I'm bad at this, but I went ahead and looked it up on the CK wiki:
"Cannot open store for class X, missing file?"
This error appears when the game tries to load a requested script, but the file for it cannot be found. Double-check that the pex file is in the appropriate folder (Data/Scripts).
From what I can tell, it looks like the script that controls the knife impact spell is missing from the mod install. I think. I'm very new to modding and even newer to scripting, but maybe the game refuses to let the spell effect do anything if the script is missing, which is causing the resistance message and the lowered damage?
Hope this helps. I absolutely love this mod, and I'll be happy to see it back on its feet again.
Edit: By the way, with the projectile recovery stuff, maybe you could look at the way Bethesda does it. There's a conjuration spell, I think it's called "Spectral Arrow" or something, that shoots a ghost arrow every time you cast it, though I don't know if you can recover those arrows, either.
