Compositing 4 render layers together

Setup link

Hello, im currently working on a project and im rather stuck with the compositing of 4 render layers together.
The render layers are working as im getting the propper images for each layer ( each sphere is located on a diffrent layer )
however after combining them all together the front part is clean, but each sphere is translucent and barely visable I have assigned a material index for each background ( tree, sphere, ground plane ) but i’m unsure how to use it in the compositing it all together to get a clear image.

The render layers are setup and rendered wrong.

Put the foreground, middle ground (trees), and background elements on their own layer, and render with alpha transparent background. The spheres on a fourth layer. You can then easily combine the spheres with the tree layer with Z combine node, and everything else with alpha over.

If you need to distinct each sphere, enable object index pass and give each object an unique index.

its not about the spheres themselfs, what im after is each window ( from camera point of view ) having their own story one part will show a winter theme, one spring, one summer, one autumn

took the idea from https://www.youtube.com/watch?v=YeEnc5khwzo , bigger on the inside then out

I believe I have added this to each