[thstone]

Can you post a picture of the car on the wheels so we can see the ride height? Or can you post a pic if the entire shock body so we can see where the lower collar is within the ride height range?

My best guess is that the ride height was too low. Then the pre-load and valve stiffness was maxed out in an effort to keep the car from bottoming out and when the shock valving is set a little bit softer, it goes right back to bottoming out. Again, I can't see all of the settings so this is just my best guess.

If you want to try making some adjustments yourself, then start by setting the ride right to the factory height. Then lower the car by 20mm. Then set the preload. This should be a decent starting point and the car shouldn't be bottoming out. If it does, then there is something else going on that needs investigation.

If it was me, I'd take the car to a shop that has experience in suspension setup and have them do the initial setup. Then you can adjust from there to your liking and have a known reference point to come back to.