I’ve been testing our bulbs on various platforms and have landed on the Home Assistant integration. It seems like there is some incompatibility with it and many of the z-wave RGBW devices out there (as you guys have experienced).
First off, getting the tunable white slider to show up in the interface is one obstacle. I was able to get it by adding this to my configuration.yaml file:
homeassistant:
customize:
# Add an entry for each entity that you want to overwrite.
light.inovelli_lzw42_rgbw_bulb_level:
supported_features: 19
I’m not a Home Assistant expert by any means, but I’ll keep digging. If anyone else has any suggestions, I’m open. 
For open-zwave, I’ve put the config files in our github and opened a pull request against their repository. I’m pretty sure the fix to this issue isn’t related to the config files, but rather a change to be made to the core of open-zwave or Home Assistant.
Config files in our repository for manual config:
Pull Request for open-zwave