Themes with the zip. format from what I understand will only work so many builds. At some point, they will no longer work and they have a habit of not theming areas of the ROM. Not everyone has the issue but when I flash a zip, it doesn't change any of my icons. If I flash one and then a different one they mess up. Only started happening once the new format was introduced.
Sent from a Droid to a Droid...forum