I already downloaded!
Pay attention if you use this file as the field order differs from the order displayed on steemit.com. The display order of the keys in steemit.com is:
-Posting Key
-Active key
-Owner Key
-Memo Key

It's a good place to keep the keys, your own machine! :D
p.s.: If you know a little HTML, you can edit the file with notepad and fill the span tags with the keys.
p.s.2: I complete my first transaction BTC -> STM -> BTC very cool!!!