1) If the user is authorized to see the file (either via NTFS or DMS, depending on what system you are using), he/she will see the document. To be able to open the document, the user needs to have a CAL.
2) On the server tab you are giving people a Named CAL. With a Named CAL you can open all documents you are authorized to open.
On the document tab you are giving people a Document CAL. A Document CAL is a relation between 1 user and 1 document. Assuming the user is authorized, he/she can now open that document (and only that document).
If your system also has Session CALs and the user is not using QlikView very often, you do not have to give the person a Named or Document CAL.