Please Note this is not being submitted for the artwork. Its being submitted to help xsplash creators see and learn a new method for xsplash animation.
Okay here it goes: I did this xsplash screen by basically going backwards. Using 50 images total for the effect. The base image was 500 x 500.
I placed the full image at the bottom of the throbber. Then I cut a 10 X 10 square from the dead center of the image. Then placed that above the last image. I continued to take 10 pixels off for each fram from the center point. (Hint: Use GIMPs history and go back to where you did rectangle select and add an additional 5 pixels to each side.) I continued until I had all 50 frame points in the throbber filled.