I've had this problem for a while. After I resize and orient my images in my image editor, XF often uploads one or more of the images 90 degrees out of the saved orientation. No rhyme or reason that I can observe either. I just uploaded 18 images, all the same size, and all but 3 of them loaded 90 to the left or 90 to the right. Not sure if any of my settings have anything to do with it - can't see how but here they are... Wow. It just did it here too.