The download package for this project is wrong. Instead of "Nested Data Type" you've attached the package for your "Compare Items with Remote Site" plugin.

If the proper package cannot be provided -- e.g., if the project is not complete or no longer maintained, I'd suggest marking it as such, and in either case, removing the Compare Items package from this project to avoid confusion.

If the project is real, it might be helpful to provide a link to a Source repository so someone might benefit from it regardless of its current state. :)