[Customizr theme] Enable/disable slide centering on any device switching issue

I am developing a site where the slider images although the right size 1170 x 500 pixels are effectively being zoomed in on.

I found that disabling the “Slide Centering” is supposed to cure the issue. However, when disabling instead of the slider I just get a spinning cursor.

“Appearance -> Customize -> Responsive Settings , uncheck Enable/disable slider’s slides centering on any devices”

I tried removing and adding the slider again, but same problem.

Could be a bug, but any ideas to add a slider without slide centering would be appreciated. I do have another site using Customizer running slides which was started on a previous version last April, so it must work. Tried switching themes and even reinstalled WordPress.

Thanks.