I would like to update microG Services Core, but the installation fails because of “conflicting package exists”. I figure this message is due to the fact that I have microG in Shelter.
How can I update both microG, one in Main and the other in Shelter?
It wasn’t a MicroG update but a Google Play Services update. MicroG has the same codename so Aurora thinks you have Google Play Services installed.
It’s normal to have an error message if you try to update, and no I don’t think it has done anything bad. (Since nothing has been installed/updated, Aurora should tell you that the update is still available.)
No need for a Google account for MicroG to work so yes if you have installed apps that need Google, they are probably using MicroG. Go to Settings > MicroG > Google Cloud Messaging and you will se the list of apps using it.