Migration from Core Integration to Custom Component

Introduction

The migration from the Core Integration to the Custom Component will require some manual steps. The biggest challenge is, that the entities for your devices will have different names. The exact steps might be dependent on your current setup. You can find a discussion on this topic here: https://github.com/danielperna84/hahomematic/discussions/881:

Taken from the topic mentioned above, a possible solution for a clean migration requires the following steps:

Delete the legacy integration and all orphaned entities left over in HA (restart HA multiple times to find all)
Take the time now to go into your Homematic UI and tune the naming of all devices here. Find a systematic naming so all devices follow the same pattern. Mine are generally names from big to small: Bedroom ceiling light or Livingroom lightswitch entrance. Avoid special characters (like the German äöüß)
Set up the new HA integration and check that all devices/entities are named to your satisfaction
Go through your automations and dashboards to see what needs to be updated to match the new devices. Not only because of names, but also to address changed behavior, e.g. of thermostats.

The process will take about 1-2 hours. But this depends on the amount of devices you have, and can therefore also take more or less time to complete.