Hello!
All I know is that the LimeWire teams uses the application InstallAnywhere from Zero G's version 5.06 Enterprise build 1671 to create the installers.
http://www.zerog.com/index.html
However that is not required to open a finished LW installer. All that you have to do is to drop the downloaded LimeWire bin file ontop of Stuffit Expander (version 6.5 or later is required) icon on your desktop and it will drop a functional installer on your desktop that you can execute and install LW from.
If it does not work then you have either downloaded the wrong version of LW that is not for your system. If that is the case then you have to download the proper version from LW's site. Another possibility is that your download became corrupt and a few bits got lost during transfer. If that is the case then you have to trash it and once again download a new copy and hopefully you will get a functional installer.
And as I mentioned you have to use atleast version 6.5 of Stuffit Expander to open it so check the version you are using. If you are using a version that is 6.5 or above then it is probably the other problems mentioned in my post or in the posts above that is the cause of your problem.
Another possibility is that you downloaded LW from another place other then LW's site
http://www.limewire.com
Maybe you have recieved some kind of developer version of LW. Make sure that you download LW from LW's site.