Well, the one about the false positive was the one you should have read.
That one had the info that you needed.
The vps is the database that hold all the detection strings.
How to set update options depends on the connection and what the user want.
All update options are described in the help/manual.
Also have a look at the options the avast4.ini file is giving you.
There is a whole thread about it from Tech with a lot of usefull information.
I suggest you take some time to make yourself familiar with how Avast is working and what options/settings it is offering the user.