I also received Zulu today and can confirm that the main movie is not region coded. It also has the usual Cinemascope aspect ratio of 2.35 to 1 despite having been shot in Super Technirama 70.
further insight taken from Widescreen Museum - The Technirama Wing - Page 3 showing the frame marker
Technirama® vs Super Technirama® 70 Image Sizes
There is often some misunderstanding about how much image is lost in one dimension or other when Technirama negatives make 70mm versus 35mm prints. The 35mm screen ratio was 2.35:1, as per CinemaScope, and the 70mm ratio was 2.21:1, as per Todd-AO. This is not a very great difference. Since the camera negative in the Technirama system created an image with a ratio of 2.25:1, both formats could be extracted with virtually no image loss, as clearly indicated in the sketch above. The extraction areas are so similar that it would not be necessary to use separate camera finder markings in order to protect action within the frame, though the finders actually did have such markings. Please note that the indicated areas are not the exact extraction areas used by Technicolor, they are simply an illustration of how little the difference is between the available extraction areas.