Write to contacts on Xamarin.Forms

Hi,
I'm trying to write contact information into their respective address books. I've seen examples on reading contacts (still haven't managed to get it to work, none of the examples compile, have to spend hours resolving bugs to get it to work!) but is there anything out there to write to contacts?
From the AddressbookSample (https://github.com/softsan/AddressbookSample) , Xamarin.Contacts does not work. Xamarin.Mobile does not compile.
Is there any way?