Splash screen is a pretty complex thing, hard to maintain and offers absolutely no benefit other than eye appeal, which is the reason we dropped it off the distro. But if you want to restore it, here are some things you should look for.
After building the plymouth stuff, you will need to rebuild the initrd. Your new initrd will need to include the plymouth binaries and related libraries as well as video drivers (modules) for your video card.
Once that is complete, you will need to probably edit a couple of init files (maybe rc.S and/or rc.M)
This is NOT exactly a howto, as you can tell is a pretty general idea of what is involved, which might serve as an explanation of why we dropped it. Even when this is successfully and properly setup, the bootsplash was a hit-and-miss for us. It would work for some users, not for others and would sometimes have undesired side effects (high cpu usage and consuming system resources come to mind)
Hope this helps (maybe?)
