Since you're working on this again (yay!), I thought I'd do a better job explaining what's gonig on with the texturing:clicky
So apply face and values should 1) be default behaviour and 2) apply the exact value of the source face (in this example 0, 0 shift). I don't know why it isn't.
It's much more difficult to explain what it's doing with world and face alignment. It doesn't seem to be predictably replicatable, but it's certainly not maintaining a 'world' alignment when applying texture and values. It's like it's trying to match the exact normal-projection of the source face which is... inverting the world alignment? Or something? I honestly have no idea.
Basically the problem is I don't feel like I know what alignment or values my target faces have when i'm texturing. I know it shouldn't matter - if it visually looks okay, then why bother? But all I can say is my OCD hates it and it's really putting me off using Sledge as my main editor, which I totally would otherwise.
I think potentially even keep the behaviour it has currently, but make it its own mode like 'eye-match source face' or something. Apply texture and values should just
apply texture and exact values.