custom post subscription for public subscribers

Hi,

I’m trying to find a plugin that would allow public subscribers to choose what kinds of posts they get from our site:

I have a web site with regular posts and one custom post type (e.g. “mathmemos”) and multiply categories in regular posts and categories in the custom post type. My first priority is finding a way to allow visitors to register for new posts and/or “mathmemos”. If possible, it would nice for visitors to select which categories they would like updates on within posts or “mathmemos”.

We are currently using Jetpack Subscriptions, but it doesn’t support custom post types. I have looked a number of plugins (Subscribe2, Subscribr, Better Notifications for WordPress, Email Subscribers & Newsletters…) but I can’t find the combination of options I need:

– subscription to new posts (not notifications for WP users on web site events, though maybe this could be repurposed)
– support for public users (no WP account, only a simple email submission)
– support for custom post types
– support for categories
– ability to import 150 current email subscribers

I know just a little bit of PHP and can make changes to functions.php in a child theme, but I don’t know how to write a plugin or anything like that.

Here’s the site: http://www.collectedny.org

Currently, regular posts are being sent out. Custom posts published at http://mathmemos.org (same site) are not sent out.

Am I miss something simple? I’m starting to tear my hair out looking for a solution.

Help would be much appreciated.
Eric