Did you solve this Neil?
I’ve also got a Dimmer 2 that won’t dim.
Originally I had normal bulbs in it, but having just installed a bypass module, I’ve now installed dimmable LED bulbs.
But, using the App I can’t get them to dim.
Have set parameter 13 to 2 (auto-calibrate with Bypass module), but it’s not getting set back to 0 again, which it’s supposed to…