GFK, i had the same problem of some objects falling through the landscape.
Ive just been through the terrain tutorial briefly (find it here!) and you have to set the maximum number of collisions that can happen at any one time, i guess its exceeding this value when you see the objects going through the terrain.
Ive just been through the terrain tutorial briefly (find it here!) and you have to set the maximum number of collisions that can happen at any one time, i guess its exceeding this value when you see the objects going through the terrain.