Arelith

As far as I tested this. The ability does not trigger the bonus damage, at any range, when using a ranged weapon.

The custom on-hit scripts of assassinate only work for melee weapons.

I'll look into editing the feedback messages for the assassinate command to be clearer on this point.

It doesn't say "melee only" in the assassin update notes or on the wiki. This really needs to be clarified if that is the case. I have to now scrap a ranger/assassin I've been leveling if they don't get assassin benefits and I've seen people recommend ranged assassin builds in the past so I don't think it's common knowledge.

... can they be retrofit to work on ranged weapons? Seems weird it wouldn't.

After reading it only works for melee weapons. I tested some more and can confirm it doesn't work for Unarmed combat either.

Is this intentional? The suggestion forum is locked, but I'd say this should work for all weapon types, at least at the same range that sneak attack works for all weapon types.

It does, but you must have some fighting gloves on it as it applies an on:hit property to your gloves or main hand weapon. Standard bracers don't work (for example the 5/+3 bracers are not valid).

You can see the property on the weapon/gloves after you use the ability.

Ah, right. Gloves. Then that works. But it still doesn't work for ranged weapons.