Q. Can collisions be set up?

A. We are sorry, but this add-on does not have collision setting function,

You will need to set it separately in Blender's physics properties.

Q. How can I center the cursor with the splash

A. As a basic operation, you can move the 3D cursor to any position by Shift + right click.

Or how about the following?

(1) Create a cube separately from the water splash.

(2) Subdivision modifier on the cube

(2) Shrink wrap modifier on the cube

　└Select the water splash

　└Offset to the outside

(5) Select cube

　└Right click → Move origin to geometry⑹

⑹Shift + S long press → Select “cursor as selection