I'm guessing you could use Near Infinity to mod the Backstab.2da file as well as a few other files.
If you own the game on Beamdog you can also sign up to get the beta. Just looking at it internally it looks like its been fixed (I can't check the beta at the moment to confirm this).
This mod brings the backstab multiplier progression to match the progression in BG2:EE. It does not include the HLA's, so you can't get them if you use an XP cap remover.
Comments
If you own the game on Beamdog you can also sign up to get the beta. Just looking at it internally it looks like its been fixed (I can't check the beta at the moment to confirm this).
I personally use this:
http://forum.baldursgate.com/discussion/24699/bg-ee-updated-shadowdancer
This mod brings the backstab multiplier progression to match the progression in BG2:EE. It does not include the HLA's, so you can't get them if you use an XP cap remover.