If you can't find any solution to this issue. And that means even seeing if there's any update to your installshield engines: http://consumer.installshield.com/kb.asp?id=Q108322 & also http://consumer.installshield.com/kb.asp?id=Q108158

Then as a last resort, dwnld the LW international installer. It's a much larger dwnld. It's disadvantage is it forces LW to use Java 1.3 which is a little out of date. But it does use a different type of installer.