Summerboard works for changing icons only on 1.1.3. To install it, you have to trick the installer to thinking that you're still on 1.1.2. Here are the steps to making it work:
1. Connect to your phone with WinSCP.
2. Navigate to /System/Library/CoreServices
3. Edit SystemVersion.plist
4. Change version to 1.1.2 and save.
5. Go to installer(no reboot required), and install SummerBoard.
6. Change SystemVersion.plist back to 1.1.3 and save
7. Move your Themes to /private/var/mobile/Library/SummerBoard/Themes from /private/var/root/Library/SummerBoard/Themes
8. Restart your phone and set your theme, you will notice that the icons will work.
Changing the Dock Manually:
1. In WinSCP, navigate to /System/Library/CoreServices/SpringBoard.app/
2. Rename SBDockBG.png to SBDockBG.png.old
3. Copy your dock file into the folder and rename it to SBDockBG.png.
4. Open SMBPrefs and restart SpringBoard.
If anyone knows which file is the SpringBoard background file, I would appreciate it so that I can add that to this "tutorial".