There's no reason why you couldn't keep both the old Grasshopper for Rhino4 and the new Grasshopper for Rhino5.Grasshopper for Rhino4 will never expire.The new installer should not uninstall Grasshopper from Rhino4.The new installer will put Grasshopper into ProgramFiles(x86)\Grasshopper for Rhino 5\ or into MyDocuments\ depending on user privilege levels.If you already have Grasshopper (released on September 28th 2012) running on Rhino4 and Rhino5, it's best to ignore this release.Here are some details, facts and suggestions in no particular order: You can download the new installer from the usual location. There was a snag which prevents us from releasing an updated version and we won't be able to fix this until Rhino 5 SR1, though that shouldn't be all that far off as we've already been typing on SR1 for several weeks. Today we are re-releasing with an updated installer that will install Grasshopper on all Rhino 5 installations on a system, be they 32 or 64 bit. As of today, Grasshopper is officially a Rhino 5 only plug-in.
Grasshopper and Rhino 4 no longer get along and Grasshopper has decided it's time to move out.
