You are putting it on in the correct orientation. You wouldn't want a gap between the sprocket and wheel hub that would warp the sprocket when you tighten the bolts. As to your question about the locking tabs. They make no sense to me either. The only way they would work is if the holes in the sprocket that the bolts go through were threaded. Since my bike did not have the original sprocket when I changed mine out, I don't know if that is the case. I'm not too worried about it though as mine does have self locking nuts on the bolts so even if they were to work their way loose, I would realize the issue long before it left me stranded somewhere.