Ok, thanks alot for the quick and precise help.
I followed the instructions, seems to work somehow, but now i can't access the runeui at all.
There is no login window popping up, just the browser saying that it cannot connect to that specific ip.
I just saw that nginx brings up an error message "nginx: [emerg] unknown directive "auth_basic" in /etc/nginx/nginx.conf:43"
Any idea? I double checked the lines being written exactly as mentioned and being at the right position...
(I'd also like to set the password in mpd, is there a way tu put the needed line in /etc/mpd.conf so that it stays there?)
->It worked to just add the line, just hadn't thought about that runeui can't be used then anymore

and a bit sad that i cant use the mpd configuration part of runeui anymore.
But since i prefer those mpd clients, i'll do it that way.
Why isnt the mpd password function implemented in runeui? Seems like a nobrainer to me, since its seems like an easy thing to do.
Again, a feature request, so that the thread is still in the right subforum
The question about the webserver not being reachable with the .htaccess active, is still of interest.