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...