Hi Michael,
In answer to your questions:
1. Microthemer saves the CSS changes to an external stylesheet at the following URL: [your domain.com]/wp-content/micro-themes/active-styles.css
This external stylesheet is unaffected when you update your theme, or any other plugin. And so the styles will still apply after updating. There is no need for a child theme, as the styles are already stored in a separate place.
2. Divi provides a quick way to add content, and some styling options. Microthemer just provides more. It specialises in styling content already on the page, and so provides an arsenal of styling options that can be applied to any elementm including headers, footers, and sidebars. It also makes it easier to style multiple elements on the page in the same way.
Our video tutorial demonstrating Microthemer’s deep integration with Beaver Builder shows how it complements a page builder like Divi in general: https://themeover.com/beaver-builder-and-microthemer-winning-combo/
Deep integration for Divi and Elementor will be added in future BTW.
I hope that helps.
Cheers!
Sebastian
