1. On the Customize screen turn off the Use default mobile theme option under Advanced Options. 
2. Remove the stash logo from your website by getting a Full License.
3. If you still need help check out our help section or the theme documentation.
1. On the Customize screen turn on the Fix Theme option. 
2. You can also try to turn off HTTPS/Encryption in your Tumblr Blog Settings. https://www.tumblr.com/settings/blog/your-blog
3. If you customized the HTML code of the theme you may have broken it so I suggest redownloading or using Tumblr's Theme Recovery.