@tevez1986 – Thumbnails not rotating can be fixed by forcing “clear image cache” in Next-Gen Gallery -> Other Options -> Miscellaneus. I’ve tested this on the latest version. Regenerating thumbnails in gallery manager doesn’t work, also manually cutting the thumbnails doesn’t generate a new thumbnail, only clearing the cache works.
@photocrati – It would be nice if your team could patch a forced thumbnail cache clear for rotated images, so you don’t have to do it manually every time.
Tested this on localhost (xampp) and an external site on WordPress versions 3.9.2 and 4.0