1. Sorry about that, in some configurations it is a bit buggy.
2. I have tried it, but it appears okay on my screen. You appear to have a very strong caching enabled (maybe cloudflare?), and this will cause the changes to propagate very slowly. Make sure to clear every cache when you change the plugin options: site cache, page cache, asset cache, CDN cache, cloudflare, browser cache etc..
3. It is possible to enable it on the Layout Options -> Content Options panel. I have enabled it for you, you should start seeing the plugin under the posts content: https://i.imgur.com/60KskNn.png
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