Not sure if something has gone wrong but ive just completed the preload and I hav 4 VLC media files of about 4gb each. The GOG downloader showed that there was 31.5gb to download and I know that I only downloaded 16gb today as I had the downloader infront of me while watching a movie.

Are these 4 media files correct?

EDIT
OK downloader said it was complete so I cleared The Witcher 3 from the list and re-added it. Its now downloading the last 6gb of files. LOL, I'm having a nightmare downloading this game on GOG for some reason :)