Some other issues I just came up to:
When one uses Cyrillic letters for the title, the slug gets such letters too and that leads to 404 error. Here, try this: “Тралала!”
No matter how many tickets we got, Manage Tickets button in the admin bar keeps showing (0).
We got two different configuration pages, right? https://site.com/wp-admin/admin.php?page=fst-admin-config and https://site.com/wp-admin/admin.php?page=fst-config . Well, okay, but the second one displays “You do not have sufficient permissions to access this page.” when I’m the administrator of the website.
Last but not the least, I uploaded a php file, but it renamed it to jpg… obviously not an adequate one. Uploading script is in fact quite a security issue.