I know this issue is years old at this point but I have figured out what's up with snap orientation. The OVRGrabber script gets the object's rotation offset by multiplying whatever you put in the snapOffset GameObject with whatever the rotation is in gripTrans (found in the grip transform option within the OVR Grabber component)... which has a default of (0,0,0). Set the gripTransform's rotation to (1,1,1) in the editor and you'll be able to get snap orientation to work.
The jury's still out on snap position, though. I'll come back here if I ever get it figured out.