Problem description: The diagram in the preview image includes 5 parts/options, but after I downloaded it, it contains 6 parts.
Reason: In iSlide V3.3.0 and later, some of the diagrams offer numbers/parts option. That means, a diagram might offer several options of parts, for more flexible use.
Solution: Decide the diagram you want and select the numbers as needed.
For example, if I need the diagram contain only three parts, I will click on the number of "3":
if I need the diagram contain five parts, I will click on the number of "5":