Please update this awesome plugin

I think this plugin is great. I have it working on one of my sites, after sorting out an issue with indexing in newer PHP versions. (I think it was replacing curly brace indexing with square brackets in markdown-extra.php). However, even with this fix for some reason the plugin doesn’t work on a new site I’ve made. It would be great if you could take a look and make the plugin work on modern versions of WP. It’s quite unique in the way it converts to HTML for the DB then renders as markdown when editing, making it more robust than other solutions I’ve tried.