Before-the-Bell: Multimedia Games Drops  NEW YORK (Reuters) - Shares of Multimedia Games Inc.  &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=MGAM.O target=/stocks/quickinfo/fullquote"&gt;MGAM.O&lt;/A&gt; fell 19.5 percent before the bell Friday a day after  the developer of games for casinos said it will post  unexpectedly weak fourth-quarter and full-year results.