What I want to do is create a PS action that would be able to add a designated background to a masked PSD file. For instance, if I photograph 10 basketball teams but we aren't able to do the photos on the court because it's being used, so I shoot them on a chroma key BG and cut them out with the intention of adding a "court" background.
Once I have all of the masking done, I generally batch downsize everything a small amount so that they are all of uniform size making it easy to just add the new BG into each photo (I generally downsize because the largest I'm going to print would be 8x10). Here is where I would like to run an action to add the BG instead of having to open all of the files back up and add/save manually. Any suggestions?

