The VST plug-in shows up in Kore when you launch it after loading the AU one in Logic (the AU one doesn't). Kore itself takes up about 20% CPU (which isn't really 20% since there are two processors) and about 62MB, but it seems to work fine. And it certainly solves the output problem.
So I was able to load Vienna Instruments plug-ins in Logic and Kore while running a stand-alone player too.
So I was able to load Vienna Instruments plug-ins in Logic and Kore while running a stand-alone player too.