No, only the main runtime has to be called runtime. All external "runtimes" in Poser 5 can have any name. As soon as you add a folder to your libraries from within Poser, the program will create the necessary folder structure... libraries/character... libraries/pose... Those new "runtimes" can have any name and can be located anywhere on your computer. Even on CD/DVD.

Yesterday's the past, tomorrow's the future, but today is a gift. That's why it's called the present.