Multiple mediaOuts with alpha from Fusion to color page

I have a sky replacement that I did in the color page, and I want to be able to color grade the sky separately from the foreground in a single color page node tree. However, when I add the additional inputs on the color page for the other mediaOut nodes in Fusion, what was alpha in those clips is now black. How can get the alpha to stay with the image? I don't see an option to add alpha inputs, just alpha output.

Do you have it connected like in my example below?

I didn't have it set up exactly that way, and changing it to how your example is set up fixed it. I am confused about something though: why do you route the background image's alpha to the alpha output and not the foreground image's alpha? The way I had it set up was with node 01 (in your example) going to the alpha output, rather than node 04, since that's the node with alpha on it at all. Why do you set it up the other way around?