Yusko,
1. No you can not change the number of images in the boot and shutdown animations.
2. No you can not move the battery icon, or the placement of any other icons.
3. Your first theme actually has more pieces than that. Each menu screen is made up of the top header, two side pieces and 4 animation pieces. The two side pieces are only one image but used on both sides.
4. If the new theme is one image 160x120 then you have to cut it into pieces to match your images. This is where the side pieces can be a problem as each they have to be the same so the xbox theme will not work as the left and right sides show different icons.
5. You can not change the position of the first area but you can make it look like it is at the bottom by removing the menu title text string from your firmware and then adding the title to the bottom of the image as in the example where e-books is written on the image.
6. Answered in 4 & 5
7. Because in one the text is displayed with the firmware font and in the other the text is part of the image.
8. If you put the same image 4 times even though it is still changing it will appear static because the image does not change. You can not change the number of images.