I'm afraid not. It has me quite puzzled. Just in-case it ends up being significant, could you tell me what your current MyBB version is? Your current PHP version (it's displayed in the debug text at the bottom of every page on your forum, if you're logged into an admin account)? Do you have any other plugins installed (and if so, what are they?)? Have you experienced this issue with any other plugins?
Also, are you experiencing it EXACTLY as Kiibakun (the reporter on GitHub) is? As in, do no templates used by this plugin display, but they do appear on the list in the Templates area of the Admin CP?
Also, are you experiencing it EXACTLY as Kiibakun (the reporter on GitHub) is? As in, do no templates used by this plugin display, but they do appear on the list in the Templates area of the Admin CP?