Movie File Out - GoPro Cineform with Alpha

Hi I am trying to export an animation with PointClouds as a GoPro Cineform with alpha background.

However it only exports the alpha, and I don’t see the pointclouds.
Just to check I exported the same file as HAP without alpha, and there you saw the animation - HAP with alpha and there again the pointcloud was not visible and only the alpha channel.

Anyone any thoughts on this? Thanks in advance!

little addition, I pulled the Cineform file to DaVinci Resolve and changed the Alpha Mode to Premultiplied or Inverted. Then I see the pointcloud however no Alpha Channel in the background.

It seems as if there are two “layers” either the Pointcloud or the Alpha Channel (?)