Hi!
The plugin should work with RTL alignment. If there is an issue with that, let me know and I will check if something is overriding the CSS.
On the Theme Options panel you can change almost everything regarding the search bar, including the colors as well: https://i.imgur.com/QNdOuJO.png
If it’s not suitable for your current site or project, you still got a lifetime license and upgrades, which you can use anytime in the future.