Marcelo, I’m not sure that’s the reason. The developers have no problem answering questions in English, there is an English description on their own website and the plugin itself is in English.
I think it’d be in their interests to also make the description on WordPress bilingual at least, so as to avoid this confusion; most plugin developers will write an English description, whatever their native tongue. It’s clearly caused at least one person to think the plugin itself must also be in Spanish!
I might contact them and suggest a bilingual description, as people should feel confident to try this great plugin.