I've just finished Witcher 2 and was eager to jump into 3. Game downloaded fine and it has patched up to 1.07 without a problem. Click Play in galaxy and it launches without a problem. click on New Game and the opening cinematic runs without a problem. Then i get a black screen with loading in the bottom right and llittle tips that change every 3 to 4 seconds....but that is all i get. If i ALT-Tab out and go to task manager it shows witcher 3 as ot esponding'.
I've verified the files, set everything to Low but am getting no joy.

Win 8.1, 8gb ram I5 processor and an AMD R9 290 card.

Any help greatly appreciated

Seems to be a common issue with 1.07. There's still installer for version 1.06 directly in your account -> library, try uninstalling the game, downloading ALL THE ARCHIVES and then installing it again. Alternatively you may wait until CDP fixes the bugs introduced in 1.07