Here’s the handler for the new Zooz zen24 toggle dimmer, version 2. The new version allows it to work with your existing standard 3-way switch, like the other version zooz switches. They are also including a neutral wire, which is very convenient.
March 31, 2018: Updated the handler to have the slider show 100%. It’s just a simple hack - 99% and 100% are both the same.
August 11, 2018: Updated to add the fast ramp parameter.
Note that there is really no way to distinguish in the software the version that has the fast ramp parameter and the one that doesn’t, but it should be available in switches purchased after 2/1/18. Just try it and see if it works.