I have developed this web application to allow controlling a CoolMasterNet from a Hubitat dashboard (or accessing the app directly from a browser).
It is not a direct Hubitat integration, but it is very useful to me. I have added it to web tiles on my dashboards.
In the future I may develop a direct integration to allow automations, which doesn't mean that this manual control would be obsolete.
Available on GitHub: CoolMasterNet-Web
PS: I know that not many people use CoolMasterNet, but it will probably be very useful to the few who do.
Example:
