Question: How to allow user to reload QV file opened from server ?
That's right. Opening on server doesn't allow you to do some things by design, one of them is reloading or editing the script.
If users are accessing the document via IE Plugin or AJAX, they will need the Desktop application in addition, so they can open the document and hit the reload button.
All users in QlikView Administrators local group (in the server where the installation was done) can access the Consoles, so they can reload anytime they're asked. This may be an intermediate solution.
Note that when the user opens a document all folders to files (QVD, Excel...) and database connections need to point to the server. This will work with both UNC paths or network drives, but with permissions enough to read files and write if there are some STORE statements.