Nuendo 5.5 Mac 64bit plugin error

In 64 bit mode, the third party plugins are not shown, only a empty plugin window with the text: “no screenshot available”.
Another error is that when you right click on a part and choose plugin; only the nuendo plugins are shown, not any third party plugins…
I’m on Snow Leopard…

PPMulator+ 3.07, installed as 64 Bit app does not show up at all, only when starting Nuendo as 32 Bit.

Christoph