yes, that's right, I need to use output of virtual device in the Rule Machine... quick search shows what you suggesting is not possible in RM Hub/device variables in rule machine?
What's the point of this app if I can't use it in RM, generally what I want is to calculate average temp and then if this is above threshold, set Hub variable to true so I drive bunch of logic in many RM rules, so may be approach is differently, how to set Hub Variable from Averaging Plus app?