Yes, there is a page which you can make available to your members allowing them to import contacts one at a time.
The page is located at: yourdomain.com/admin/contactadd
You can control how many contacts a member is allowed to add through this page per a day in advanced features.
Yes, you can edit the contents of any page in your members area through the file manager
From the file manager go to the uploads/adminpages folder (there is a quick link in the top right).
There you will see html versions of all the php pages in your system's members area which you can edit to change the appearance of the php pages in your software members area.