Skins and cpu usage

First of all, I'm most definately new here, and I thank anyone who can answer this question, or better, solve it.
Ok, as a fun exercise with my daughter, we did a relatively simple skin. It has nothing animated and checks in at only 95k in the zip (xsf) format. Bt comparison, one of the downloadable skins on this site, retrospect, checks in at near 2M in the zip (xsf) format, and comes with ample animation.
How is it, then, that my simple skin will chew up a consisten 10-12 in the cpu usage column of task manager when the player is in the stop mode?
The animations are running in the retrospect skin, and after 30 seconds of watching the task manager, xion cpu usage never topped 5.
As a third point of reference, the default skin, in stop mode goes to 0 cpu and stays there.
I have used my skin in *.psd format, in *.zip format, and in *.xsf format. I have loaded the skin after xion starts, restarted xion with the new skin, and even restarted my computer to restart xion. Always using 5 times the cpu power of a highly animated skin, and infinitely more than the default. WHY?
Ok, as a fun exercise with my daughter, we did a relatively simple skin. It has nothing animated and checks in at only 95k in the zip (xsf) format. Bt comparison, one of the downloadable skins on this site, retrospect, checks in at near 2M in the zip (xsf) format, and comes with ample animation.
How is it, then, that my simple skin will chew up a consisten 10-12 in the cpu usage column of task manager when the player is in the stop mode?
The animations are running in the retrospect skin, and after 30 seconds of watching the task manager, xion cpu usage never topped 5.
As a third point of reference, the default skin, in stop mode goes to 0 cpu and stays there.
I have used my skin in *.psd format, in *.zip format, and in *.xsf format. I have loaded the skin after xion starts, restarted xion with the new skin, and even restarted my computer to restart xion. Always using 5 times the cpu power of a highly animated skin, and infinitely more than the default. WHY?