Variables are not interpolated in single quoted strings.
<?php
$var = 'map.swf';
echo ' <OBJECT ID="map" CLASSID="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"
CODEBASE="http://active.macromedia.com/flash2/cabs/swflash.cab#version=2,0,0,0"
WIDTH="50%" HEIGHT="50%">
<PARAM NAME="Movie" VALUE=" $var ">
<PARAM NAME="Play" VALUE="false">
<PARAM NAME="Quality" VALUE="best">
<PARAM NAME="swLiveConnect" VALUE="true">
<PARAM NAME="loop" VALUE="false">
<EMBED NAME="slav" SRC="' . $var . '" swLiveConnect="true" WIDTH="50%" HEIGHT="50%" mayscript="mayscript" quality="best" play="false" LOOP="false" pluginspage="http://www.macromedia.com/shockwave/download/index.cgi?P1_Prod_Version=ShockwaveFlash2">
</EMBED>
</OBJECT>';
?>