Is there any e-mail address or someone on the forum who actually works at Serpent in Netherlands???

This is the only way to contact them as far as I know ( http://www.serpent.com/company/contact/ ). Since they are a manufacturer and don't deal with the general public, they do not publicise their contact information, otherwise everyone with a problem would be contacting them, when they should be contacting whoever sold the car/product, or the relevant distributor. Serpent is a very small company, I would be very surprised if anyone who works there is a member on the forum, and even more surprised, if they were, if they made that fact public knowledge. I know I wouldn't.

Are you looking for parts?

No parts. Just some questions concerning the 720 kit.