Got the installer working. Fixed a few bugs including a nasty-to-debug issue where the lang_id was being hardcoded during installation, resulting in strings being inserted with the wrong lang_id causing an infinfinite loop with fetch() throwing a "no strings" error and using template (which calls fetch()) to complain
.mceItemFlash, .mceItemShockWave, .mceItemQuickTime, .mceItemWindowsMedia, .mceItemRealMedia {border:1px dotted #cc0000; background-position:center; background-repeat:no-repeat; background-color:#ffffcc;}
.mceItemShockWave {background-image: url(../img/shockwave.gif);}
.mceItemFlash {background-image:url(../img/flash.gif);}
.mceItemQuickTime {background-image:url(../img/quicktime.gif);}
.mceItemWindowsMedia {background-image:url(../img/windowsmedia.gif);}
.mceItemRealMedia {background-image:url(../img/realmedia.gif);}