have to see if there is a way to turn off steam updates
In theory, to disable steam updates is simple;
Open steam library - right click skyrim and select properties - select updates tab - under automatic updates select 'Do not automatically update this game'.
In practice though steam resets this option and goes ahead with the updates for many users.
Some / most Skyrim users (depending on what you read) run steam in offline mode to counter this issue. It is reported though that as soon as steam online mode is reactivated the updates option resets and again the updates start downloading.
I have read many posts on various forums about this issue and most people affected negatively rightly (IMHO) complain that either the option is broken or that steam want control of what updates we use - regardless of our want or need to control our own computers (to a degree). Other users sing the praise of the update feature and give arguments for how good the feature is and that it is supposed to update skyrim no matter what the user wants. I ask; why give an option to not update then ride roughshod other the users preference? The answers to that vary from uninformed through fanboy to outright rude!
Anyway, it seems you have the right idea by keeping backups and using them till fix is found by one of the 'modders' on this forum.
Minor edit for rewording