Ckeditor - gtbu/Typesetter5.2 GitHub Wiki
Since Typesetter 5.1b1 (github – master), the ckeditor 4 is in the directory include/thirdparty/ckeditor (before in include/thirdparty/ckeditor_34).
All ckeditor – versions – also for Typesetter 5.1x – are available here.
If You want a different ckeditor-skin, You can install the Theme-Plugin.
If You want to make Your own ckeditor – version, You can upload the build-config.js to ckeditor.com and add further plugins. This should function with official plugins. If You also add inofficial plugins, which were written for older ckeditor – versions, You can have a malfunction of ckeditor.
It is therefore advisable to install them from within the CMS (please watch their dependencies). If ckeditor doesnt come up, You can uninstall the plugin.