yes, it's possible..
you make your macro script, select all nodes that you want to be included, with the ones you want as an input at the top hooked up to a dummy node, then select the nodes to be included in the macro, make sure that the top nodes have the input selector (green bulb) activated in the macro maker. rename them as needed and save, done.
im pretty sure it's in the manual somewhere as well.
++ chris