First of all thanks for a great app. So easy to use!!!
I did find small and (for me) nagging issue. It seems server app has a small bug determining duplicate folder names. I have my (rather large) media libary set up on ZFS share on Ubuntu 14.04. When I add first directory with HD movies (in my case /zpool1/Public/Movies_HD) it works fine. If I add other directories like TV_shows etc no problem. But when I add another directory of HD movies (in my case /zpool1/Public/Movies_HD_before_2000) it will not add the folder. I checked in Chrome developer tools and it seems like it sees this directory as a duplicate of the Movies_HD folder added earlier. If I add folders the other way around the duplicate is found to be whatever folder I add last.
Maybe you could add fix for this in a new version coming up?