Thanks for opening the topic.
I tested the problem that you reported about changes made to mobile view being applied to desktops. I could not reproduce the issue.
It would help if you could provide step by step guidelines on how to reproduce the issue.
For that, the best would be to start from a blank test page and start building a simple section with Nimble Builder.
And provide guidelines that would look like :
1-Insert a heading module ( for example )
2-…
3-…
About your alignment problem, I’ll try to provide general guidelines that I hope will be useful :
– Try to use the Nimble Builder template instead of the theme one => this will allow you to start with full width page https://docs.presscustomizr.com/article/339-changing-the-page-template, and then customize the inner / outer width, globally or for each page, or even by section https://docs.presscustomizr.com/article/396-how-to-customize-the-width-of-the-sections-created-with-nimble-builder
– Try to not use negative margins in your webdesign, this isn’t a good practice because it makes it very difficult to place elements and it’s complicated to maintain. It’s rather recommended to use vertical aligment in columns and modules ( which a setting accessible when clicking on a column or module settings ), combined with padding tweaking
– For columns, keep in mind that you can set custom breakpoint so that they stay horizontal on mobiles. You can set breakpoint by section, or for a page, or even site wide : https://docs.presscustomizr.com/article/343-designing-for-mobile-devices-with-wordpress-nimble-builder
I hope it will help you!??