I have Poser 6. I designed some animations for a particular figure and posted them for other people to use. But it turns out that people with Poser 5 (and, presumably, earlier versions) cannot use them, even though the figure they are designed for works perfectly. When they try to import them, Poser states that the animations were made with a later version of Poser, and that it will try to use them anyway, but it can't.

Now I didn't know that this was the case. It seems rather perverse that animations cannot be imported from 6 to 5 in this way even when they don't use any features lacking in 5. Is there any way to solve the problem - any conversion software perhaps?

That's strange.  I don't think 6 made any big changes in the animation
area.  Are you talking about complete PZ3 scene files, or animated
pose PZ2 files?    The scene file might have something unrelated
to the animation that's causing the problem....?

One odd problem I encountered yesterday, which 
may or may not be related: Pose files made in 7 include a 
'staticValue' line with each parameter, which can confuse 
earlier versions if the staticValue isn't the same as the 'k' value.  
I had to remove the staticValue lines to make a set of pose files
work in 4.  I don't know if 6 includes that line.