Editing the HTML that Creator exported from the Word document may be your best bet. The easiest approach is a blockquote, here is an example from
Kindle Formatting: The Complete Guide:
Code:
<p>The man from the West unfolded the little piece of paper
handed him. His hand was steady when he began to read, but
it trembled a little by the time he had finished. The note was
rather short.</p>
<blockquote>Bob: I was at the appointed place on time.
When you struck the match to light your cigar I saw it
was the face of the man wanted in Chicago.
Somehow I couldn't do it myself, so I went around and
got a plain clothes man to do the job.</blockquote>
<p class="right">JIMMY</p
The blockquote typically indents the text. Note that you can't have paragraph tags in the blockquote (turn each paragraph into its own blockquote). This isn't offset from the right edge, you can probably do that with CSS styles but I don't know how. You can add vertical spaces using MOBI-specific <br/> tags, or with margin-top and margin-bottom CSS formatting.