You should be able to log into two instances of the same account (with the same SE ID) on two different pcs. You just cannot log into the game and play on the same account on two different pcs at the same time. So go ahead and download on one and play on the other. I update on my laptop while I'm already playing on my desktop. Now, if you don't have a one-time password app/token, it will probably seem suspicious that you're logging in from a second location and lock you out. So I recommend getting the app at least if you don't have it.