For the time being, Columns layout is not supported by the editor.
As far as your other questions are concerned, when the user publishes the document
from Lightning, it will be uploaded as a single document in the selected document library.
All the pictures, data and formatting in this document will remain part of it.
What you can do with this document, is either download and preview it on you computer with an application that supports *.doc / *.docx files, delete it from Sitefinity, multiply it, etc.
The data in this document however, cannot be extracted and used as separate Sitefinity content.
There is no widget so far that you can associate with this document type.
Pictures inserted in the document will not be uploaded as pictures in a Sitefinity image library.
You would be able to access all the information in your file only by opening it again in either MS Word or the embedded editor in Lightning.
I've recorded a demo video in which I've tried to explain all the statements above in actual interactions with the application. You can watch it by following this link
I hope this information helps.
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
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