It would tell me that (image) menu_on.skin which cause me to look for it only to find it was just misspelled (mennu_on.skin). Sometimes the graphic was missing all together.
External_GPS.skin was always missing the underscore!
All this cause me to scratch my head wondering what was wrong - until i ran skinchecker!
With this version i hope to trim a lot of fat (unnecessary files and images) in some skins.