Note
For the versions earlier than 4.x.x (including on-premises ones), please follow this instruction.
In general settings, you can set the web part height and enable:
caching - the client-side caching improves Org Chart performance,
zoom - it allows to use the mouse wheel to zoom in and zoom out in the web part,
collapsing - it allows to expand boxes and see subordinates below if there are any.
Note
Go to the last step of the configuration wizard Reset configuration.