Try copying those files, there are 4 .DLL's from the Samples directory that comes with DarkPhysics into your project's directory.
You will need to make sure that you have the correct DLL version or it will give you a similar though different error.
I only say to copy the DLL's from the Sample Project's because they are the easiest to find without digging through PhysX driver folders looking for specific versions of files.
the names of the 4 DLL's are :
NxCooking.DLL
NxCharacter.DLL
PhysXLoader.DLL
NxExtensions.DLL
They should be able to be found by your project's EXE file either by being in the same folder as it, or in a place where it will look for them.
If it ain't broke.... DONT FIX IT !!!