Isn't 4.5 what came on GB release? It should be in the repository. Check the third link in my signature. There is a TW Launcher that came with stock 2.3.6.
app icons: give the .png the name packageName.png
app backdrops: give the .png the name tile_packageName.png
random backdrops: name it tileXX.png where XX goes from 0 to 15 (both inclusive)
app icons only for dock: dock_packageName.png
home icon: dock_home.png
apps icon: dock_apps.png
dock background: dock.png
and more ([URL="http://xdaforums.com/showpost.php?p=14756991&postcount=4"]menus, page indicator etc[/URL].)