Just thought i would share how i did this to get a good core of members using this plugin.
I had a bit of a challenge because i had just converted over from another script to Oxwall and so everyone had the same activity date. What i did was i sent an email out for everyone to log in and update their profile within 7 days.
Then when that time came i reviewed the results. It was not the best result but it was real. There were customers that had not signed in among those that i really wanted to keep because they were old time members.
So what i did was i logged in as admin (to set my activity date) then i went into the database and all of the people that had updated their profile i did a sql to update all their activity dates to the same as mine (timestamp). Then the few old timers that i wanted to keep regardless i manually went into each row and change their activity date to mine.
So this effectively seperated everyone out leaving those that had not signed in to update their profile with a date of 7 days ago. Then i just set the purge for 6 days just to be sure and let it sit that way for a full day. When i checked back, all the old ones were gone (140 of them) , and then i just changed the purge back to 90 days. Now i have a good core and the cycle is set.
Happy coding... :)