To protect your qvw file, you can do the following:
Backup your master file first, so that you don't lock yourself out of the file.
1. Put the whole script in the hidden script tab
2. add section access
(which answers your point 1, the user needs to log in with a username and password)
(you should set this even if you don't require a login for the user, as this will ensure they open the qvw in user mode rather than admin mode, reducing their privileges such as from editing the script)
3. In Document Properties > Security, turn off the options you don't want the user to have, in particular the following:
a) Edit Script
b) Edit Module
c) Access Document Properties
d) Show Progress for Hidden Script
Once this is done, save and reload the file before sending it to your client.
Regarding to your point 2, i don't think you can do that easily/reliably. But you could set the section access to log in using their NT Access which should limit it to specific users in the company.
Your point 3, you could hardcode a date into the load script to do that.
