When i finally made a rather difficult scene in Bryce 5 with lots of imported objects & really lot of work in Bryce itself i tried to animate it. The result was that almost every imported object and lots of negative objects went under the virtual floor, even if they where grouped. I don't know if this is a Bryce 5 bug or some kind of my mistake, but i experiment a little with Bryce 4 too & i got the same results. Sometimes i had this when i copy & paste imported objects from one Bryce file to another and press 'Undo'. The whole scene seems to explode. Can anyone help?

It sounds like you might have had the "Auto-Key" for the keyframes turned to "on". This makes tons of unwanted keyframes everytime you move an object. I suggest turning off the Auto-Key and starting over. Set key frames for each object after you have changed it's position and only set a key frame for the attributes you have changed. Animation (even on a computer) can be very frustrating and challenging. Back in the days of painted cells, most of the animators I knew were alcoholics, drug addicts, or just total flakes. Counting frames and key frames will do that to you. ;-) Don't expect to become Walt Disney overnight, it takes years to truly master it.