A couple things. You say your are all position qualed and are now doing a 6G. Is the chill ring the only difference? And when you say tie ins, are you talking about tying back into your starts?
If so, my technique with FCAW has always been that when you see the start approaching, just before you get there you jump quickly out to one of the the corners of the rounded start point, hesitating for the briefest of moments to make sure you burn in to the vulnerable corner, sweep quickly across to the other corner while concentrating on maintaining the arc right over the top of the start edge to burn anything that may be trapped, and then hesitating again at the opposite corner to burn anything out and then pull back slightly and drag out slowly. This has always worked to flatten start ties ins for me. The jump out minimizes the colume of metal, and hesitating at the corners ensures minimizing slag inslusion at a couple of the most susceptible points.
You also want to make sure you move quickly at the very beginning and build up to your fill level so that when you tie in to your start you have less metal to overcome.