I'm also uploading one of the first versions of the engine itself! This is a very early testing environment of the engine.
The controls are simple:
Click the left mouse button to start creating particles where the mouse is pointing.
Click the right mouse button to create a particle generator where the mouse is pointing.
Use the arrow keys to adjust the accelerations of the particles. Left and right add wind ("W"), while up and down change gravity ("G).
Notice that the particles fade as they move outward :)