Particle System Editor - No OG Prim Node Option

I’m trying to follow this tutorial:

I have downloaded the tutorial files and followed every instruction to the letter.

However, when I get to the point of adding the VFXShere01 mesh by dragging it into the particle editor, I do not get the option to select “OG Prim Node”.

I have four other options and have tried them all, but none of them result in the meshes instantiating on the points.

This is what yout tutorial shows:

These are the only options I have:

Any help to get past this point is greatly appreciated.

We will review the docs and get back to you asap. Thanks

Many thanks