Enable mobile theme
On the Customize screen turn off the Use default mobile theme option under Advanced Options.

Display avatar image
Upload an image to the "Header Avatar" option, square images work best.

Remove stash credit
Remove the stash logo from your website by getting a Full License.

Change Logo Image Height
Add Custom CSS under Advanced Options: .logo img { max-height:200px; }

More help & customization
If you still need more check out our help section or the theme docs.