Thank you Felix for your feedback! Please note that the most current version of the binding can be found here. Curious to see if you still see the strange behaviour with the Colorpicker with this version.
I have also a development version which fixes a bug when there is no Rhythm module connected to the Nanoleaf Light Panels, and adds experimental support for the Nanoleaf Canvas device.
Still waiting for @terriblefox (Binding Request: Nanoleaf Aurora (LED Design Triangle) to test it with his device ;-), to prepare a new pull request.