There has been a thread on the Vray forum talking about multiscatter and Forest Pro. I (tricky) mentioned that FP is great, but we have had far more crashes with Max since using it. You suggested contacting you with the minidump file.
We are running Max 2009 x64 on XPx64, SP2. We are running Vray 1.5 SP5. Our workstations have 8GB ram, but our render slaves have only 4GB. I am XREFing the FP scene into my main working file.
A scene I am working on has a reasonable number of FP objects which have VRayProxies and some normal meshes within them. Though everything runs fine and renders as expected, I am getting regular Max crashes with the scene.
I attach what I think is the correct minidump file.