Please go over the following before starting a topic:
Let's start with the obvious. This should be the first thing you check, but some don't, so here's a reminder to read the manuals!
Search the Forum
Do a simple search. The forum has been around for years. Chances are you're not the first to come across the issue. This is a technical forum so topics often deal with specific lines of code and error messages - easily searched. Alfonso even created an FAQ/How to in the forum.
The dev site includes years of ticket submissions and solutions. We have a very active ticket system with over 7100 tickets closed. There's a pretty good chance you'll find what you are looking for. You can even create your own tickets.
The API will give you an idea of how CKEditor is structured and how you can modify it.
A good place to get answers to frequently asked questions, from Open Source rules to various configuration, features and support topics.
Self explanatory. You will find a lot of results pointing you back to our forum and to Stackoverflow, so might as well bypass Google and go straight there.
Most of our replies involve doing the above for you because you didn't bother. If we find a thread that wasn't properly searched we will be... mildly miffed.