The LocalHero project website and Princes Park Touch both run on the LocalHero multisite, which uses this plugin. Open any single post or page to see it in action.
LH Related Posts by Taxonomy, like all LocalHero plugins, is built to WordPress standards, so it should work with any well-coded plugin or theme. Not every plugin or theme is well coded, though. If something goes wrong, first deactivate all other plugins and switch to a default theme such as Twenty Twenty-Five. If the problem persists, post in the support forum, which is checked regularly.
Custom work and enhancements are available: get in touch.