Sounds like the steps weren't typed-up correctly. To add the Bikini Top, use the double-checkmark button at the bottom of your Library pallette. When you hover your cursor over it, it should read "Create New Figure." Then go into the Figure menu and choose "Conform To..." You will see a window with a dropdown menu. Choose the P4 Nude Woman from the list who is supposed to wear the bikini. (If you only have one P4 Nude Woman in your scene, it's probably labeled as "Figure 1.") Click on "OK." Now, your Posette should be wearing a bikini! :)