Theme: Swift 5.62
I am using a "real" management page per your instructions. After clicking on the subscriptions management link, I noticed that the page heading ("Manage Subscriptions") pointed to a URL with a page_id of 9999999. I modified line 499 of subscribe-to-comments-reloaded.php to reflect the following.
'ID' => '1054',
It originally had the ID as 9999999. 1054 is the actual page id for my "real" management page. Now the URL of the page heading is pointing the current pretty permalink of the "real" management page instead of an incorrect page_id. An added bonus is that the AddThis social plugin that I have installed is now hiding itself. It wasn't doing this before making the change shown above.
I'm not a developer, just a tinkerer. I'm curious if this plugin could be updated to allow us to specify the page id of the "real" management page in order to not need this modification to work correctly.