Thank you for the details, helped me a lot.
There was indeed a bug related to multisite installs. I've corrected and noted the fix for the upcoming version.
I've also added a few lines of custom CSS to the search's custom CSS field, because there was an extra padding and the font size was overridden by the theme. It should work as expected now.Best,
If you like my products, don't forget to rate them on codecanyon :)