In response to post #119140678. #119166408, #119170528, #119177498, #119178018 are all replies on the same post. Unfortunate but stopping steam from auto downloading is very simple. You can set at specific time slot for it to update and it will ONLY update during that time slot (5-6 am when your pc is always off for example). This way every auto update is in your hands to manually update or ignore as you want. Lesson learned I guess, and really, if you're going to spend so much time modding and fine tuning a game it might be a good idea to learn the best way to fireguard it.
