A little tip I thought I'd share.
I've built a few compositions and made connections to the Render Scene / Image To Window node. Then I've found myself going back to that composition and bang my head on the table when I want to use the composition in other host apps. Which means I need to publish an Image, not a Window.
After doing this a few times I've started to add a "null" Combine 3D Objects / Combine Layers to my comps. That way I don't have to rebuild the scene if I choose to output to a window or an image. See reference image attached.