I have Found the answer.
the installer should be downloaded from the site as explained here:http://zeoslib.sourceforge.net/viewtopic.php?f=40&t=4955
After downloading Install into IDE gives an error that a package: ZFastCode in '..\..\src\core\ZFastCode.pas' does not exist
Remove that line from the unit as explained here:http://zeoslib.sourceforge.net/viewtopic.php?t=10886&p=25765
Build and compile and install then you should be ready to go.