TexCanaan: I've noticed several replies that mention the GOG Galaxy backup copy option. Yes, it exists. Yes, you can install your game from it. But, unlike the direct downloads from your library via a standard web browser (IE, Chrome, Foxfire), It can't be installed WITHOUT THE GALAXY CLIENT. Like Steam games, any GOG backup copy downloaded via the Galaxy client MUST BE INSTALLED VIA THE CLIENT, umless this has recently been changed.
Randalator: This is plain wrong and never was the case. Galaxy can download the standalone installers which are exactly that: standalone. In actual fact, Galaxy CANNOT use the standalone installers for installation which is the exact opposite of what you claim.
And even games INSTALLED with Galaxy can be played without Galaxy running.
At the risk of sounding like a jerk (and I don't mean to, honestly), but if you had bothered to read further along in the thread, you would have seen the post where I mentioned that I had read that information in the post of someone else. As I've already said, each time I attempted download the backup copy via the Galaxy client, the download simply failed after about 1% completion, so I haven't had first hand experience with it. Please, before just jumping on someone for saying something, read the rest of the posts. They may have retracted, corrected, or amended a seemingly false statement.
Moving on, however, I have just downloaded and installed the old GOG downloader linked in the first reply to this thread (thank you, Martek!) and am currently attempting to get my game downloaded this way. I'll let you know if I'm successful.
To anyone else who is just now learning about the old GOG downloader, to add games from your library to the download cue, simply click on desired game in your library, click the "More > " button, then click on the "GOG Downloader Links" option. Choose the appropriate link from the list for your operating system, and the game will be added to your GOG Downloader cue list. You may need to grant your browser permission to open the downloader, but that's as simple as a single mouse click.
EDIT: Having tested out the old GOG downloader, I found that, not only does it still work, but it works better that when I first attempted to use it a few years ago. This version of it didn't decide to suddenly crap out only minutes from completion, and I have already put in about 3 hours of happy gaming with The Walking Dead: Season 2. My next step will be to burn the TWD2 files to a disc, then download KOTOR2 on my next library visit. Thank you again, Martek! You've made this Good Old Gamer one happy fella! :D