I have created a module using the Module Builder and have added frontend filtering to the list of items exactly as this sitefinity blog post describes. The frontend filtering is working just fine however the built-in paging does not function correctly when any sort of filtering gets applied.
By built-in paging I mean going to backend, then going to the page where the widget has been placed, then clicking on widget edit, going to "list settings" then selecting the "use paging" radio button. The paging will work as expected until you decide to do some filtering. For example, using the "Offices" module as described in the linked post above, if you were to search for a particular City that wasn't on the first page, it won't be returned.
I believe the problem is the way the DataSource is obtained in the "SearchButton_Click" event handler (see blog post). By that I mean I think when paging is used, the retrieved DataSource when filtering only contains the items on the current page. To show how the data source is obtained, I've included the "SearchButton_Click" method from the blog post example below:
Does anyone know how to get the paging to work with custom frontend filtering? (or vice-versa)