What do you mean by bent unnaturally? As long as the rig feels comfortable while you are wearing it and is stable, then it doesn't matter how unnatural or bent it looks. You will also find that as you use it the webbing will soften somewhat and mold itself to fall more naturally into the shape that if assumes when you wear it.
And what do you mean that it doesn't fit the BP? Isn't it fitting through the slots? Or isn't it long enough? Crossing the straps usually uses more webbing so the latter probably isn't what you mean.
The strap should start out horizontal coming out of the slot at the top and slowly bend until it is vertical going into the slot at the bottom. The curve that this bend forms should follow the curve of your body under your arm and be quite natural. Have you maybe twisted the webbing by accident whilst setting it up?
And what do you mean that it doesn't fit the BP? Isn't it fitting through the slots? Or isn't it long enough? Crossing the straps usually uses more webbing so the latter probably isn't what you mean.
The strap should start out horizontal coming out of the slot at the top and slowly bend until it is vertical going into the slot at the bottom. The curve that this bend forms should follow the curve of your body under your arm and be quite natural. Have you maybe twisted the webbing by accident whilst setting it up?