Ratcheting doesn't matter, they work just like friction, but with a ratchet on the upshift. The barcon lever should be down pointing at the ground when the RD is at the smallest cog. That is the way you have it right?

Things to consider:

Is the housing moving?
Do you have tension on the cable before shifting?
Cable locked good at the RD?

Don't get caught up by the ratcheting thing...they're just levers.