When using the map of South Africa, you’ll notice there’s a lot of space at the bottom. This is because the map includes the Prince Edward Islands.

The Prince Edward Islands are part of the Western Cape region, legally.
​https://en.wikipedia.org/wiki/Prince_Edward_Islands

The map shapes are provided by a library that generates them automatically with the geo data available.

So that’s why to fit all the country in the viewport, it ends up looking like that.

When using the pro version, it’s possible to use the options to change the initial zoom and center, using the following values:

You can set a different initial zoom and a different center with coordinates if necessary.

This way you can change the viewport to focus only on ‘mainland’ South Africa:

Another workaround would be to use a custom geojson map, with this custom SA map file.