Anyways, I can't give you a quick fix for this unfortunately, I will have to investigate this one in more details – as other mobile devices does seem to work okay. I will definitely fix it for the upcoming release though.
2. There are 3 exclusive grouping options, it's not possible to mix them. If you only search products, categories and tags, then either post type or content type grouping is the best choice.
The only thing to do here is to perhaps change the 'Other results' header text to maybe 'Results from categories and tags' or something like that: https://i.imgur.com/n50F5M1.png
If you like my products, don't forget to rate them on codecanyon :)