function displayFlag(flagToDisplay) {
    document.envoyPlugin.setCurrentPage(flagToDisplay)
    document.envoyPlugin.executeCommand(601)
<FORM NAME="myForm">
<EMBED NAME="envoyPlugin"
SRC="http://www.tumbleweed.com/evy/flags.evy" WIDTH=300
HEIGHT=250
BORDER=0 INTERFACE=STATIC ZOOM=fitwidth 
PLUGINSPAGE="http://www.tumbleweed.com/plugin.htm">
<H2> Select a flag to display:</H2>
<INPUT TYPE="radio" NAME="flagToDisplay" 
onClick="displayFlag(1)"> U.S.
<INPUT TYPE="radio" NAME="flagToDisplay" 
onClick="displayFlag(4)"> Germany
<INPUT TYPE="radio" NAME="flagToDisplay" 
onClick="displayFlag(8)"> Canada
<INPUT TYPE="button" NAME="test" VALUE="Get Number of Embeds" 
onClick="alert('Number of embedded plug-ins in this document: ' 
+ embeds.length)"