Have you tried calling the customer service number of Elica (the manufacturer)? Here is their contact page:

https://www.elica.com/US-en/contact-us

Yup. "No technical advisors are available, please call back later" 

Thanks though

Only a well-filtered hood exhaust should be recirculated. Does this assembly come with one, besides the mesh filters facing the cooktop? Does it provide a means of filter replacement? Is there a duct to outside?

With respect to the lever, perhaps closer examination of this spot will prove fruitful.