I've also downloaded GOG.com Downloader, but it shows no games. Any help, guys?

Ah. Welcome to GOG. Where since the launch of Galaxy client, new users tend to be confused.

For downloading by using Downloader, you need to open the website -> Log in -> go to your Account/Library -> select the game you want to download, it'll open the game information. (I assume you already arrived at this step before)

Now go to More > GOG Downloader Links > choose the file you want to download. Usually "Windows installer, English" or other version in different languages. It'll start GOG Downloader (if it is not running yet) and the download process.

Edit: added pictures for example of the process

Somebody push the button to call in the Top Men.

I seriously recommend to let this thread rest in peace.
It was about a piece of software that has been dumped years ago and it never was about the Google Play store.

It's a bot, and it has been reported in the relevant thread.