Hi there.
I tried to get this Boulotaur injector working too, but to no avail. However, whilst trying, I came across this tutorial that got everything working for me.
https://youtu.be/ZHGd1wwyILI?list=WL
Note that this does not in fact use the Boulotaur injector, but uses RadeonPro, which is a program that does a lot of stuff we don't need, but also has SweetFX support.
Also, don't be scared by the name "RadeonPro". It works with NVIDIA too (I myself have NVIDIA).
My specs:
Windows 8.1 64-bit
NVIDIA GeForce GTX 970
Gr Rupture13