Check for poetry or other indented material. Mark the end of each line with **.
Exit Word, saving the file under a new name (so that the original remains in case you really mess things up), and choosing "text only with line breaks".
Go into PRTK. Choose Processing, then post-processing, then Misc. Load the new file (bottom right of the screen), then check off the first two options: remove end of line spaces and change lines with only spaces to ^p. Run the program then exit PRTK. (Note: ^p is the end of paragraph or 'hard return' character in MS Word, your mileage may vary.)
In your word processor do the following. a. Select everything from the beginning of the text to the end of the file. b. Change ^p^p to @@ in the selected area. c. Change ^p to space in the selected area. d. Change @@ to ^p^p in the selected area. e. You now have text that will fill to the margins with the spacing between paragraphs preserved
Adjust the size of your page so that there are 65-75 characters in a fixed-width 10 pt font per line. SAVE the file, choosing "text only with line breaks". Search for two spaces together and change them to a single space.
While doing the above, you will find the indented material. Delete the ** and insert a return, making sure that the overall formatting looks OK.