Oooh that's Galaxy doing its auto-update thing.
Which it does by downloading the raw uncompressed latest version, it doesn't download the .exe patches.
Again, downloading the patches and such via the website or via Galaxy is purely for backup purposes.
Or saving some GBs since the patches are compressed.
I'd suggest letting it keep downloading, I think otherwise you'd have to download the base game installer again.

Damn. And there's no way to increase the speed of the download from a pitiful 0.2mbs?

Well you can go to Options (the little gear icon below the game list on the left) and see if the 'Number of Concurrent Connections' can be increased.

I don't really use Galaxy so I don't know, but I assume it supports resuming your downloads.
If that's the case you could try fully closing Galaxy (so not just to the system tray), waiting a bit and starting it again.
Perhaps it needs a restart in order to use the new config and you might connect to a different download server.
Again I've never tried it, but logically it might work ;)

I've tried that as well - I've restarted it a number of times, to no avail. Looks like 0.2mbs is the best I can expect.

You can also try the good old downloader. Go to the account in the site and select Downloader links.

But now I'm confused. I thought the previous person said that downloading the patch from the website (which I'm assuming is via the 'downloader' app) is not the right way to go. The game is downloading the patches for the first time, since I installed the game for the first time today (well, yesterday now).

I would suggest using the 'Reply' button when replying to someone's post, this will add a special icon next to the topic and sometimes a notification for that person. It makes it much easier to know if someone is trying to communicate with you.

Sorry I'm just confused by the whole thing now and I really don't know what to do or not do. It's taken 7 hours just to download 3.7gb and there's another 13gb to go. It's just frustrating.

I'll just have to leave it to do it's own thing, regardless of how many days it takes. I don't want to screw anything up.

I get it, unfortunately this is very much a place where if you ask ten people a question you'll get ten different answers.
Mine was based on all the information you posted.
You could try using the downloader beside Galaxy for a bit to see if you get a much better speed.
Just don't cancel the running download before you know.
And you might need to do a rollback to a specific version in Galaxy in order for the downloaded patch to work.
And you would probably need to turn off auto-updating while you did all that.

It's been more than half year and the problem is still there.

On just part 2/8 of the witcher 3

2.1/4.0 GB, 1 hour left.

FML

I also have this bug.
Thought I'd try it to get some local backup copies of some of my library games but the speed is rediculously low.

It is oscillating between 0.3 MB/s and 0.0 MB/s (yes zero point zero that's right).

My direct non-galaxy (ie browser) downloads are typically at 2.1 MB/s.

I've noticed GOG is downloading really slow too. I used to be able to download about 4 MB/sec, now it's at less than 300 KB/sec. Are they doing some kind of maintenance?