UM... NO! You don't want to unzip to your Poser "Runtime" directory. You want to unzip to your Poser directory itself because all the zipfiles file structure already includes the runtime directory. If you unzip to the runtime directory you'll end up with a file structure similar to this one:

C:Program FilesCurious LabsPoser 5RuntimeRuntime.....

Simply unzip to either your Poser 5 directory or your poser 5 Download Directory if you want to keep it separate from the main runtime.