I am having my own problem with getting the login to work.. I can get in, but only if I follow very specific steps.
For clarity, it should be noted that I am running nginx with my xenforo and my wordpress on separate subdomains. For extra fun I'm also using WP in it's multi-site network mode.
site.tld: /var/www/wp-website
forums.site.tld : /var/www/xenforo
So, when I am on a blog page of say,
www.site.tld/site1/blog/ and I see the "you must login to comment" option I click it and I am redirected to the xenforo login page correctly at forums.site.tld/ That works great, but there is no "redirect back to where we just were" action happening, if that makes sense. Basically the user has logged in to make a comment, and is now on the forums page.
If I manually go back to the blog post and refresh, it does recognize my cookie and allow me to post. It's just not the clearest method.
I assume this is because there's nothing on the xenforo side saying, "if you came in this way, follow the additional redirect arguments back to the wordpress". However it could also be that I simply have something misconfigured on the wordpress side and maybe it shouldn't be directing me to the real forums at all?
Not sure, guidance would be awesome
I use absolute paths personally.. since I have a dedicated box it's the easiest method. So for me, my path is: /var/www/xenforo/