Please make sure to finish all your posts before this time. The downtime should only last for a few minutes.
No stash icon
Open a new tab and look at the top of the Speed Dial. You should see a button to access Stash.
In Windows Stash is also accessible via the main menu. I don't know where/if it's located in the Mac OS X menu...
You add pages there by pressing the heart icon in the address field when you're browsing the desired page.
The stash icon is visible in your screenshot. It's in the address bar displayed as grey heart.
I think the user doesn't know how to access the Stash page.