Did you look in the examples directory in the plugin?
There is a description of how I implemented this Police Department / Fire Department filters in this post on my web site.
Mike thank you for replying and for supporting such an incredibly brilliant plugin. I did look at your code samples a few days ago and was hoping to skip adding any extraneous user data. Is there another filter that I could use to filter users based on post or postmeta data directly?
P.S. When trying to view your site tonight I got a warning and an attempted redirect to an unrelated site.
I have resolved the redirect – thanks for the heads up on that. Not sure what happened there.
Creating your own filter would be done similarly to the example I’ve provided. You need to setup a query which does what you want, namely return the user ids for those users who have posted 5 or more times.
I am not sure how you construct that query but assuming you know how to do that, the rest of the example is applicable to the results returned by your query.