Hi!
I wonder how can I scatter few cars in the scene and get a motion blur on them. I tried CoronaScatter along spline and animate offset to move them without motion blur effect. There is the same problem with ForestPack, there is no visible motion blur. Does someone had a good solution for this? I really have a lot of cars to move 
Thanks!
Motion Blur won’t work with scattered objects, a known limitation. That would mean doing something other than scattering them (by Corona or other scatter tool), or perhaps applying motion blur in post in a video editor.
Maybe try to use pflow to move your cars? That should work with MB.
… or use Civil View. It’s actually build for this (amongst other things), and MB works fine with it.