i don't know if it's the link that causing the error. because it's the first time i encountered this error. i'd been updating my copy with this default setting and updating just fine.
I'm sure that it is the link that you're using that is returning those bad gateway errors, if you change the link to the correct one it'll work. You are using a "git link" and you are trying to pull from a svn, you need to use a "svn link" or change the link that you are using, or it will never work.