I cannot figure out how to edit a file on-line using Writer, and then check that file back in.

The source is a Word doc that I uploaded.

I checked it out, and saved another copy in the source folder, but cannot figure out how to merge it with the original.

Shall I tell my team the only way to make edits and check them in is:

1. Checkout

2. Download to local

3. Edit

4. Check in with the upload as new version option

???

Thanks.