I have not talked to my sysadmin yet, but I don't think they have blocked spotify especially.
I was under the impression that setting a proxy URL and port should be enough to get this working? I've read in some other thread here that another user had a problem of spotify disregarding the proxy settings and trying to do some connections without using the proxy in the beginning, might this bug still not be fixed?
I am quite sure that I will not get any exceptions added to use spotify, but it should be enough for the in-app proxy settings to work for me to use Spotify, or do I miss something there? I can use the web-player just fine for example, but in my usecase it's not sufficient for me and I would really like to be able to use the native application as it supports more features.