If you want to add a segment / chapter to supplement with information that does not fit into the predefined parts of the service, do as follows:
Put PM in "Edit mode"
Go to the segment you want to add a chapter to and place the mouse pointer above the heading you want the segment / chapter in front of
Move the mouse pointer so that the plus sign and a frame appear
Click on the plus sign and you will come to a box with the following choices:
Title - click on it and enter the name of the title
Free text - add a segment under a heading where you enter free text
Picture - you can "drag & drop" pictures to PM by dropping a picture where there are plus signs. You can also select "Image" and choose from the computer which file to upload
Page break - you create a page break where you selected
When you are done, set the PM to "Read mode" again and Save
Now you have a new segment / chapter that is included in the PM and which can be seen in the table of contents etc
