Hi,
"... what about Laubwerk, MaxTree and VizPark? Do they come with own addons for ForestPack?"
Yes, these third-party vegetation models comes with its own Forest Pack integration in the package itself (and with all instructions needed how to install them).
"... what about stand alone plant meshes - can they be implemented to custom libraries and the FP Proxy system?"
Sure, any model inside the 3D Max scene can be used as a
Custom Object under the
Geometry tab - if your
Merge (or link as a
XRef) any model into your scene and then create a Forest object, it can picked as a
Custom Object.
Also, please feel free to create your own libraries. I would suggest you to check the "
Creating Libraries" tutorial covering this topic in detail.
Hope that helps.
Best regards,