Thank you for your rating and feedback. :)
The warning basically only says that this feature is not supported in the version you are using (1.9.4). Our approach at the time was to issue the message every time so that this would not be overlooked.
However, we have already changed the whole thing so that this is only issued once at start. This change will come with the new update.
You can either deactivate the function in the config or use this dev build, where the whole thing is already adjusted:
https://hub.yourgamespace.com/jenkins/job/AntiCooldown/132/