Hey there! I'm very new to the community as well. I have a feeling a save function will be added eventually. In the meantime, I have been writing my drafts in word then using an online html converter when I am ready to post. Something like http://www.textfixer.com/html/convert-word-to-html.php
There are plenty of converters out there. Of course, you still have to add your photo's and edit everything, but at least you don't have to start from scratch.

There may be a better way that I am not aware of though. I am still very much a newbie!