I see a panel that cycles between a Sid Meier-related railroad sale, and a "War for the Overworld" sale. The Overworld link works, and resolves to a normal "here are the Overworld games" sale page. The railroad link does not work, and It just steers you back to the front page, where no Sid Meier game is listed. Here is the busted link...

http://www.gog.com/promo/20170814_special_promo_railroad_games

Maybe it'll get fixed.

UPDATE: I thought maybe you had to click through the link "categories" like THINKING, or ROLE PLAYING games on sale, but I looked through them all. No railroad games. Rollercoaster games, though! :)

GOG staff OFTEN do similar stupid things.
For example, the 2nd phase sale of last week have wrong countdown. (They fixed it after half a day.)

GOG's promo often have wrong timezone, wrong countdown, wrong URL, wrong discount.

One would think they would check these things at least right after posting them, let alone get it right the first time. Apparently, nobody can be bothered to do so. For as big as GOG is these days, even for a niche business this is embarrassing.

After over 20 hours, GOG finally fix the bug.
https://www.gog.com/promo/20170814_special_promo_railroads

UPDATE:
GOG staff make wrong timezone AGAIN. (They OFTEN make similar mistakes.)
Sid Meier's Railroads & Railroad Tycoon promo showed
6D, 05:46:03 at homepage, but showed
5D, 23:46:20 at promo page