Ok, I downloaded the kozaburo Morphhair, and I downloaded, unzip all as per his instructions, but in the preview window all I get are dots/mesh/, but no preview. What am I doing wrong?

When transparency is on the element looks like that in your Poser window and only after you render you can see it. Try this: go to Display > Element style > Cartoon with lines (I don't have Poser here in my office so I'm not sure of the exact words...) and you should be able to see the form of the hair prop. You can also go to Render materials and turn the transparency to 0%, so you will see the hair. Just remember to turn it again to 100% before rendering. I hope I have been clear, my english is not that good...

Wireframe style seems to work well when dealing with transmapped hair, also.

For ease of use, the Document Display Styles have hotkeys. Use CTRL-3 for Wireframe, CTRL-7 for Cartoon-with-Lines, and CTRL-9 to return to Texture-Shaded style.

OK, it is the final render that counts. So why worry if you can't see it in preview mode? Just render it and you will see it!