@Paloth: I experienced a similar problem. In my case I had to install Java ( http://www.java.com/en/download/manual.jsp ) because it was missed somehow by the browser (IE, which is needed for Poser's library). I only found out because of IE. On the link you'll find the right thing for your OS. In my case, I'm on WinXP Prof 64bit, I had to restart after installing Java and suddenly the P8 library worked. Even though I did not find a hint about it in the forum, I hope it will solve your problem too.

And be aware If you use 32-bit and 64-bit browsers interchangeably, you will need to install both 32-bit and 64-bit Java in order to have the Java plug-in for both browsers.