If you're creating the skull cap for personal use then you can spawn it directly from the figure's head using the grouping tool. 

Use the grouping tool to select all the polys you need for the skull cap, then click the "spawn prop" button and the selected polys will be duplicated into their own object at the correct size and placement. Then just save it to your Props library (in your own custom folder to keep things organized and you don't confuse yourself later). You can also save it as a smart prop by first parenting it to the figure's head. Hair room hair doesn't need rigging, so the skull cap can be a smart prop. Once you save it to the Props library you can delete the original from the scene and reload the new one from the library. If it's saved as a smart prop it will automattically load parented to the figure's head. 

The only drawback is that you can't use this skull cap for redistributing. For that you would have to make your own custom cap in a modeling program and then bring it back into poser and make sure it fits the figure by manually scaling and repositioning. 

ETA: Good that you upgraded to 2014. With all the work you're planning, you won't regret it. IMHO 2014 is the best version so far especially for content artists. 

 

~Shane