Same flare appearing in two diferent cameras

Hi there!

So, I've been using the Space For Unity kit to build my space scenes, and that kit has the ability to create, among other things, local stars. This creates skyboxes by using a Space Camera (that never leaves the point (0,0,0)) to render the background (on the Layer 20 - DeepSpace, flags set to Skybox), and the Main Camera (Flags set to Depth Only) to record the foreground (everything else).

In the middle of all that, there's the local star flare, which not only belongs to the DeepSpace layer, it's light Culling Mask is set to only light everything in the same layer.

However, that flare is appearing twice! Even though the Main Camera Culling Mask is set to everything BUT the DeepSpace layer, and the Space Camera Culling Mask is set to only see the DeepSpace layer.

This one shows the relative positions of the cameras and their output: And here notice how there's two flares, the extra one slightly to the left of the other:

Sooo, any ideas? Thanks in advance, João Borrego.