Imported IKEA group will not work with color temp

To solve some communication issues with larger light groups I turned on this feature to make use of the groups defined in the IKEA app:

tradfri:
  host: 192.168.x.y
  allow_tradfri_groups: true

After a reboot of HA/reconfigure IKEA integration the groups are discovered. However the only options available is to turn them on/off and set the brightness.

I can’t set the color temperature!

The groups only exist of the same lamp type that do have this capability. It is working via the IKEA app or using HA light groups. (Only the last one I want to avoid because of the communication issues with larger groups)

In developer tools the imported IKEA group is reporting for supported featured: 33, all lamps that are part of this group have 35.

Any idea how to set the color temp to imported Ikea lamp groups?

UPDATE:
An additional issue maybe the underlying cause? I just found out that the IKEA integration is now discovered twice! Maybe once via the “normal discovery” and the 2nd one via the configuration.yaml additions that is required to turn of the group import. I also notice the current groups are imported but nor working at all. (turn og/off is also not working)

2nd question, how to properly configure/integrate with IKEA if you want light groups enabled?

It seems not possible to enable the “allow_tradfri_groups: true” to the configuration.yaml without adding the IP of the gateway. And this results in double discovery.
The auto discovered one can’t be configured to allow tradfri groups.

How to proceed?
And do Tradfri groups work with brightness & color temp?

Anyone to get the “allow_tradfri_groups: true” setting to work properly?