@klaey. Thanks for posting. I would love to help you. However, i would need to see the web pages with the problem. Also, you need to give me some more details of what it going on.
From what I know, persons get error 500 pages if they don’t access the list via a menu page alias. Also, you can give me temporary admin on your site, if you want me to look at your site personally. Just email me the details if you are interested in doing that.