I'm not certain if this is happening with anyone else but, whenever an update happens for the game, I often find the next time I boot up SK after the update, it'll start 'updating' with a pack as large as the game itself, about 300 MB. I have uninstalled/reinstalled and it doesn't seem to fix this issue. I have a bandwidth limit so this is very very annoying. :/

And yes, I am running off of Steam; it downloads itself via Steam when this happens.