Anyways, considering the skill CANNOT be charged, it should not get stuck in the charging animation indefinitely in such a scenario but rather immediately execute it. As you said, it should be on button down instead of button up.
Having brought up the same point on the discord, people brought up the fact that you can cast barrier onto other players using a targeting reticle, hence the reason for it's cast on button up not button down. So unfortunately that means 1000+ hours of guarding experience takes the override for me
1. This applies to 100% of all keyboards ever.
2. The keyboard is still sending button presses, but a different code is sent depending on whether numlock is on or off. For the purpose of this game it should treat them both as the same button, which I have seen some games do
That doesn't seem like a bad idea actually, though I don't know if those buttons are consistent across keyboards of all different languages. However the thing that's intriguing me is what happens when you bind a key to what would be the key underneath? My keyboard doesn't even have a NumLock button despite the fact that it has an entire numpad, though it's not a detriment when all the buttons that would be underneath (being arrow keys and Ins/Del/End/Home) can be found just to the left anyway. Ultimately it seems like a lot of hassle from something very trivial when you could just like, not hit NumLock
One thing I either suggested somewhere else on the forums or on the discord is that, if you've got a keyboard setup like mine with WASD for movement and NumPad for skills, that you put your most used skills close to where your fingers are. I normally have my main 3 on Num1/2/3, potions on Num5, bow on Num6 and the lesser used skills on the top row.
And if your fingers are generally on the top row, move your fingers. As a lot of the keyboard is actually fairly similar you can generally move your entire hand by a bit (such as changing Shift + WASD + Space to \ + ESDF + Space) and still have the same finger placements, it just takes maybe a half hour of remembering to put your hand in the right place.