Well I can confirm that adding a runtime wher eV4 has already been installed works just fine. Ever since Poser 4 I've installed everything into that (PBooosted) runtime and it still works today, 10 years later L - including V4.

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You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
  Using Poser since 2002. Currently at Version 11.1 - Win 10.