I never use the ICON method. I only use the Bundles Method. here's a quick walkthru:
First use a program like iFile (iphone), Iphone Browser (desktop) or AppInfo (app) to find the info. I prefer Iphone Browser when working themes but iFile does the trick well just slower.
Drill down to:
/var/mobile/Applications (used for App Store app's)
/var/stash/Applications (used for Cydia Store app's)
for both, click on your app, i'll give an example for BiteSMS:
drill down to the correct folder stated above, click on:
biteSMS.app
scroll down to Info.plist, click to view and look for:
CFBundleIdentifier: used for Folder Name
CFBundleIconFiles: used for icon name, there may be multiple here but for IP4 use the "@2x" one.
Now that you have that info you'll need to create a subfolder inside the Bundles folder of your theme's Directory in Winterboard found at:
/var/stash/Themes
Name the folder using the CFBundleIdentifier: com.bitesms (my example)
copy over your preferred icon inside this folder and rename using the CFBundleIconFiles:
icon@2x.png (my example)
After this is done, its safer to go into Winterboard deselect and reselect your theme to have winterboard reload your theme icons and respring. If all done correctly your app will be themed.
Few tips: Watch your capitalization. Its case and space sensitive. Triple check your naming. Some people like to respring after adding a subfolder but i found it unreliable. Sometimes the app icon doesn't change. I always re choose it in winterboard. And be sure to use the correct icon name for your device: a.e @2x.png or .png
I hope that helps. Its a bit confusing the first time but after that its a piece of cake. I hope i didnt confuse you more
