If you're experiencing any download problems, especially download corruption, please redownload your game by using the "add to GOG.com Downloader" option, found on your My Account page, right below the regular browser download links.

The new GOG.com Downloader now features full error-correction functionality and thus should be able to cope with any download corruption issues, as well as offering the fastest possible download speed. Most importantly, it can pause and resume downloads, so it's perfect for large downloads and unstable Internet connections.

In case you experience any problems with the GOG.com Downloader, please drop a report here.