I’m confused as to where I lost you.
Let me walk you through what happened…..
My install was 100% perfectly normal.
I installed your plugin.
*Immediately* after clicking the “assign” button everything broke.
Yes, literally the whole thing.
Not just that particular plugin.
Simply put: after trying to save the changes with your plugin, that’s what killed it.
I, personally, did not change any other settings. Unless if your plugin did. And that’s why I’m reaching out to you, because obviously you should know more than I do about what your plugin is intended to do.
In the meantime, after sitting with Hostgator tech support twice, for a combined total of over 3 hours, the temporary solution is to disable multisite entirely.
If I enable multisite again, everything immediately breaks in the same exact fashion that it broke right after saving the changes inside of the plugin (with the permanently redirect to wp-signup.php).
This is not just a coincidence. Your plugin changed some other “core” files and I’m here because I don’t know what they are, but you should.