It would probably be better if you changed your "CKSource support" to "CKEditor support". CKSource is the company that creates CKEditor, CKFinder and several integrated versions of both for different platforms. Some of these products are Open Source (like CKEditor), some are only available as commercial products (CKFinder).
CKEditor is our flagship product, it always was and will be Open Source, so this is probably what you want to support.
Re: Supporting CKSource (our way)
CKEditor is our flagship product, it always was and will be Open Source, so this is probably what you want to support.
Documentation Manager, CKSource
See CKEditor 5 docs, CKEditor 4 docs, CKEditor 3 docs, CKFinder 3 docs, CKFinder 2 docs for help.
Visit the new CKEditor SDK for samples showcasing editor features to try out and download!