Version 2.1.9.1 not Working propperly, and issue with layout

Hi, so this new version made impossible to change the configurations:

Fixed Price
Use SESSION
Switch Currency by JS
Some things in Currency Options
I cannot change to Location, Checkout, Design, Price Format, and Update

Also, the layout in the Widget is with a white background, and it wasn´t this way in the last version, also all setting were working, I would like to know if it’s possible to rollback to the last update or to have a new update fixing these problems, I tried troubleshooting the plugin and in fact, it´s not working, I don´t use cache plugins as well.

Thanks