Please be aware that if you download the 4.1.4 zip file without images, then you will miss this image which is critical for the CKEditor: images/editor/sprite.png
You do need to upload that file. In addition if you are using non-standard Image Path setting for custom styles, please make sure you upload that file to the appropriate 'editor' for your custom style.
Check and make sure you have the image sprite.png in the editor folder for your custom style.