The overall rating reflects the current state of the app. It accounts for all app reviews but prioritizes the most recent ones.
Had some issues with getting the app to work but actually, I think it was more my side ;)
Developer jumped right away to provide direct help which was amazing. I'm really impressed.
As for the app itself - it's almost perfect. Only two things I would kind of like to do is not have a button and a link and to be able to have several 'bars' so one for EU, one for US etc.. but it works for my needs now.