Working on it. Like you, I find the aircraft overly sensitive with small control movements. I am not certain if it's a HS CL650 issue or an X-Plane issue. I have tried several different curves and stability augmentation settings. I have watched the X-Plane video by Austin. I'm playing a bunch of different configurations. Still playing...
I have always found any X-Plane aircraft to be somewhat oversensitive. FlightDeck2Sim's commented on this as well and had noted that some aircraft have a significant, noticeable delay between elevator control movement and actual elevator movement. He commented on this in the FlyJ B737-200 on a recent live stream flight in Saudi Arabia,and made the comment that he has noticed it in other X-Plane aircraft as well. I do not know whether this applies to HS CL650. I raise it here because he's a pretty well respected source for real world flying and simulator flying and his reflections on X-Plane aircraft resonates with my experience. I may have 12,000 hours and 9000 hours in turbojets, but no one knows me from Adam.
Not taking anything away from HS CL650. It's the best flight simulator aircraft for any platform (XPlane, MSFS 2020, FSX, P3D)...period!
Rich Boll