Deploying Kirby on OS X Server 5 - Reverse Proxy Issue

So just in case someone is running into this again. In the current version (2.1.1) there only needs to be a small change made to the auth controller. (panel/app/controllers/views/auth.php) In line 8 and line 30 change:

go(panel()->urls()->index());

to

go(panel()->urls()->index() . '/');

This will also be fixed in the upcoming release.