1 shouldn't be necessary if you have fastDL, or in fact even have an addons folder, but I'm not 100% on that.
2 Pretty sure the official ULX people response to this will be: we don't do game mode specific stuff, if you're requesting an addon, search the forums, there's a TTT one, not sure about any other game modes though.
3 Ditto, but search the forums, there's at least 2 that do this.
4 See attached files. If the folder in your /addons/ folder doesn't work, then just stick the .lua files in your modules folder in ULX. Not ideal, but I'm lazy.
EDIT: Did you not already make a thread on this stuff?