EDIT: Nevermind, it does the same thing with Underlord. Both games (base TQ and TQ:IT) are in english, the fanpatch installs sucessfully, at least it looks like it does, yet when I replace the files it stills bugs the game with those "Tag Not Found" everywhere.
EDIT2: Allright, problem solved.
http://www.titanquest.net/tq-forum/t...-Tag-Not-Found for people interested. Thanks for your help.