Buffer visualisations not rendering

Hi.

In the past, to render occlusion etc, I’ve changed my view mode to the buffer visualisation I need and rendered the sequence out.

For some reason this now isn’t working. I’m using 4.16.

Whenever I do a render, it renders out the colour pass. For once pass I got the pass material from the engine content folder and put it into the post process material slot.

However, this didn’t work properly for the occlusion cos it didn’t render with my occlusion settings.

Does anyone know what’s going on?

Thanks