Ok, I know this is going to sound really, really strange but I have a possible solution for you.  I'm assuming your running Poser under some manner of windows.  If so, run check disk on and then defrag your hard drive.

I know that sounds really weird, but here's the deal.  Poser is a serious memory pig - it gobbles up more memory than applications with 10 times it's memory requirements should.  As a result Poser makes very heavy use of Windows "virtual memory", which in truth is really little more than a big swap file that is written out to your harddisk.

If this file becomes corrupted it can cause some really strange things to happen inside of Poser when it runs.  So first try closing all your applications and schedule a disk check for whatever partition you run poser on, I'm guessing it's probably C drive.  Reboot your machine and allow chkdsk to do it's thing.

This can take a fair amount of time, especially if you have a big drive.  But once that's done defragement the hard drive, start Poser again and see if that doesn't do the trick.

You got THAT right! But I went full toot, did a disc check, defrag, virus scan, spybot and adware scan. I'm not paranoid, but something was killing me on this one program. Whatever it was, it seems to have cured itself partially in both P6 and P7. I still can't figure out the cause, which is my main concern now. I applied a BVH to V3 with some wild moves, using dynamic hair, and it all stayed in place! OK, one-for-one, so far.

Now if the 'Drop Figure to Floor' was a function built into the keyframe editor ....

Thanks a bunch for the replies from all whom responded.

JP