Gustav, i was watching this auction as well. I don't think i can answer all your questions, but i'll tackle a few.
To my eyes this looks like a fairly nice old Bali or Lombok keris. The narrowness of the blade does not seem that unusual to me. I have a couple of Balis with narrow blades such as this. I don't think the bladec has been re-shaped. I have seen a great number of earlier Bali blades without jenggot. It does look like it probably has what remains of an old Bali stain, but it is fairly worn out and originally the blade would have been darker and more contrasty.
I am not sure about the uwer. I wasn't even sure that this was a separate piece or just part of the hilt. The hilt form is somewhat unusal, but very beautiful and well executed IMHO.
I am sure there will be other opinions.
