Elenarie: Its not just the antivirus. For the games released in 2008 and some in 2009, from what I can tell by looking at the installation scripts, they were intentionally delaying the installation in order to advertise the service more (I could be wrong as I couldn't see the Code section, but there was definitely some delay introduced in the Setup section (talking about script's sections)).
(2008 and 2009 games are the ones I've noticed this delay with, it could be present in games released in 10 / 11 / 12 too.)
No, what you're seeing is the free games. We *do* extend the install time a little bit for them; since most of the free games are downloaded by new users and we're paying the costs for download, remastering, testing, support, and goodies for you, we figure it's not excessive to make sure that you see a couple slides about who we are while they install.
Any game that's not free that you've purchased legitimately from GOG.com that's running a little bit slow on install is a bug and you should probably drop a ticket to Support about it. I asked Gowor, our build ninja, about this and he's confident that it's only the free games, though.
