There's 2 ZIPs files available: 2.79 and +2.80 versions. Choose the one you need (or both) and install it through the user preferences window.  

The Metaball Composer will add a new submenu and 3 operators in the add -> metaball menu:

There's common settings for the 3 composition types, but elliptical and spirograph have their own specific parameters.

Common settings

• Metaballs: number of objects in the composition
• Pattern: List of available pattern types
• X, Y, Z limits: Size of the composition
• View Resolution and Render Resolution: see Blender manual
• Scale
• Use last metaball position: Instead of using local 0 coordinates, each metaball moves to the next position adding up previous coordinates.
• Use Zig-Zag effect: Just a 1/-1 multiplier
• Use 3D cursor: Use the 3D cursor as a starting point

Random pattern

 Random pattern type uses the common settings only.

There's no extra parameters.

Elliptical pattern

Elliptical pattern uses 4 functions to calculate the metaball position:

Sine, Cosine, Tangent and simple displacement

Spirograph

Besides the functions mentioned before, Spirograph also uses a minimum radius and a maximum radius to create the geometric patterns

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