https://player.vimeo.com/video/750286754?h=5b32b0c51d&badge=0&autopause=0&player_id=0&app_id=58479
Enabled by default, the direction for the particles is shown by an arrow representation in the viewport.
This arrow icon can be rotated using the usual Cinema 4D rotation tool.
The nxGravity arrow icon, having been rotated.
The strength of the gravity.
By default, the modifier always moves the particle down in negative Y direction.
However, you can enter negative values here which will move the particle up along the world positive Y-axis.