First regarding the saved file loosing all the formatting, I presume you are referring to HTML file format. Well unfortunately without more information I cannot say for sure why this issue occurs to you but I presume the problem may be that your output file uses external css, have you tried using only inline styling?
Nevertheless regarding the word documents you'll have to convert them to HTML content in order to display them in any WYSIWYG HTML editor (this includes CK editor as well). In case your documents are all newer (DOCX format) I would suggest you to try this out:
Transform DOCX to HTML/CSS with High-Fidelity using PowerTools for Open XML
If you need the solution for both old (DOC) and new word format then I'm afraid there is no free solution (at least not to my knowledge). Well... there is Word's automation which I wouldn't recommend you to use on server side.