Ah! Very good eye about the tinted white thing. I mainly was testing this in the compatibility renderer for the web demo, and I assumed that the white tint in the forward renderer stuff was just due to lighting changes in different renderer modes, so thank you very much for telling me this. I do find this specific difference here to be rather odd though.
Secondly, that's a tricky task. Firstly, the Skeleton3D and its bones are made dynamically at runtime, so you shouldn't be able to attach a bone attachment in the editor I don't think. You should be able to do something like that via script, which seems to be what you're trying to do, though as your code highlights, you'd need to essentially shrink it by 100 due to the method that I've shrunk the PaperSkeleton meshes, which is just shrinking the meshes after they've been created. I didn't have the foresight to consider that people would need to actually retrieve the 3D bone positions in certain scenarios, which, in actual world space, outputs as multiplied by 100.
While I could recommend workarounds, I want this addon's usage to be as accessible as possible, so I've released an update that I hope should resolve your issue. Here's a devlog regarding it:
https://bunkwire2x8.itch.io/paperskeleton/devlog/914403/11b-update-shader-and-bo...