Thank you for the kind words!
1. Yes, exactly.
2. Not yet. This feature was requested by many, I'm definitely going to implement it as soon as I can 🙂
3. Not neccessarily, it works without the index table just like in older versions. You can use the index table engine as well, but you will have to configure it first under the index table submenu page. Think of the index table engine as a different way of looking up results – the plugin basically will use it's own database table of generated keywords to look through instead of the whole posts table. It's a huge CPU saver for big databases. I strongly recommend reading all four Index Table chapters in the documentation to get the idea what exactly this is, and how it works.
4. Statistics database contains all the keywords that had been searched for with the plugin (if the search statistics is enabled, on the Search Statistics submenu). So if you have the statistics enabled and someone searches for “xyz”, then it's logged.
5. By default it will look in the page Title, content and the excerpt (if available), so you don't have to put keywords anywhere. You can configure this on the General Options -> Sources panel.
6. Yes, there is. The rounded edges in web-development are defined by a property named “Border Radius”. On the Theme Options -> Overall box layout panel you can define this border radius: https://i.imgur.com/3IvV6CI.png
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