1 Q & A
Q1: Can't set pip source on Windows
A1: I can reproduce but if I add the --user flag it works fine, e.g.
This makes sense, the "pip.ini" in "Program Files" is for all users and would need admin privileges to edit, you should be writing you the user level pip configuration.
Also this isn't really a pip issue I don't think, this is a Windows permissions / Python Windows Store issue.