Looks like part of the problem at least may be the battery as the heli flew different with a different battery. Be sure your batterys are fully charged. You would be wise to get a better charger like one of the thunder chargers from X-Heli. Nuttcaze has a vid on it under Batterys and Chargers.
But be SURE to limit your flights to no more the about 6 to 6 1/2 minutes. Otherwise you will ruin your lipo's and quickly.
The thunder charger will allow you to see your individual cell voltages before you start, during and at completion of your charge cycle. This allows you to know how long you can fly safely on your batts.
You of course might have some adjustment problems, but I don't know much bout coax helis. I'm sure one of the other folks will chime in shortly and help you out.
Hope I've helped you some,
Donnie D