I think I finished this a year ago and no one commented. Since then a buddy of mine @Nerbert put out a modification, so I never bothered with turning mine into a modification. I have radically changed it since then, just kind of modding as I need features. I started the code before vBulletin included theirs, in fact I have never looked at their implementation -- I probably should, maybe I will learn something.
@nerbert's modification is very good as a base and it will quickly get you going. I recommend it! If you have any issues with @Nerbert's modification, I am always around and I will always talk code. Make sure you thank him.
I think the only thing that @nerbert's modification is really missing is enlarging. If I remember.
P.S. - It is a real time saver if you are constantly trying things out and making small changes.
--------------- Added 31 Jul 2014 at 15:46 ---------------
I am currently -- very slowly as I have time -- implementing CKeditor4 for vbulletin4, just for the kicks of it. It will never be released here, but I am happy to share the concepts and code fragments with others that might want to attempt it. vBulletin extensively tests their code, I do not have that luxury and editors are a sensitive area, so releasing or displaying the code on vBulletin could lead to an exploit on someones site.
I use to use photopost for a gallery on my daughter's board before my own programming out paced theirs. It lacked a real editor at the time -- I think they just recently (last six months) added MCE --, and so I implemented CKeditor4 and styled it more like CKeditor3 so as to not upset the users. I have also implemented CKeditor4 for her mobile platform. After working out most of the bugs on the current platforms, I have decided to implement a rendition for the main board. Currently, I have been trying to figure out away to make it switchable via the user so that I have a larger testing base with the new editor, yet give them the comfort of the old editor for everyday use.