I want to add some badges to users on our community, for example a 1 Week badge for those that have been registered for a week.

Is there any way to trigger a badge based on just the amount of time they have been registered? I can see I can do it when they log in and check then but there are a couple of problems with that, firstly I want to use it to encourage people to log back in in the first place and secondly it will then go an award that badge to the 20k+ people we already have registered for more than a week 🙂

There doesn't seem to be a "New Users Only" condition?

There is no way in which to count only new users unfortunately, no. You would indeed need to put a trigger before you can add a milestone such as how long. So you would add "When member logs in for the first time that day" then add the milestone of how long they have been registered

I'll steel myself for the moaning from our more vocal members 🙂