Been trying to get this to work for weeks. Enabling individual caching options, like 'Minify' or 'Database Cache' with default disk settings fails 4 out of 5 times - the page reloads on with the checkbox unchecked again, or enabling one disables the other. Eventually, everything stays checked, but the next time you visit the admin, it's unchecked again. I have no idea if any caching is working.
Recently, an annoying newsletter-signup popup appears on every screen, and nothing you do will make it go away.