When you are making your poster a standard poster or a combination poster the poster may come out blank. This is because of the person you selected as your staring person, you will need to select a starting person who is closer to the beginning of your line. Someone like you, a child, parent, etc. These posters are trying to fill in the poster to include the starting person's ancestors. If you choose a starting person at the end of your line, the poster is not generating anything because you do not have ancestral information for that person.