There are a lot of UML Diagrams besides the well known use cases, and class, activity and sequence diagrams. Those other diagrams are not so common, so not all the diagram tools for UML include them.
That's the case of the UML Composite Structure Diagram. For example, DIA doesn't include it. WhiteStarUML includes it, but I don't like it because it is not intuitive. It is maybe possible with yEd as we can create forms with our own images, but I wasn't able anyway.
Do you know an intuitive tool to create this diagram?