Download Link

For Windows

Download Nexus Torrent Fils
 If you want to be absolutely sure you should install Nexus 2 clean then import each expansion and skin available
delete your existing Nexus 1 content folder
 uninstall Nexus1
 install Nexus 2
 install all expansions and skins
That’s it! Done.

Download Mega Link

For Mac

Download Nexus For Mac
 System requirements: 
PPC G4 800 Mhz or Intel 1.5 GHz 
512 MB RAM 
Mac OSX 10.4.x and 10.5.x 
VST, AU compliant host