Quote - is this a common problem?

No idea.

Having had a try at this, unchecking "Group figures as single meshes" seemed to be what was needed.

Make sure you have "Use external binary morph targets" unchecked when saving from Poser.

Remember when asking questions, give plenty of information.
You can tell what's likely to be relevant from other threads, but which version, and what options your using for a particular operation are generally going to be important.