I know it's not exactly a Striking issue, but Striking has a great forum, so maybe I can find someone who has an idea of how I could fix it.
It seems some Striking style is overriding the plugins configurations. At first I thought it was just a plugin issue, but I had the same problem with three plugins: Basic Google Maps Placemarks, WP Google Maps - Pro, and Multi-column Tag Map.
In Info Windows (with Gmap plugins), and in the entire index (with Tag Map) the words are without style and in Info Windows they don't respect overflow, even if I try to put it as a CSS line in the General page box.
It's solved now. The problem was that the theme was wrapping the code. I changed to html and deleted the words [ code ] [ /code ] and it all worked fine.