I've created my own action in Photoshop CS5 and in my example I am recolouring grass.
The action stops for the user to paint a selection on a layer mask and continues with a colour balance adjustment.
The action then continues to use the selection mask from the first layer and another mask is created, this time the user adjusts the hue/saturation.
On occasion, after I've changed the hue/sat there are some areas on the masks that I've missed. Is there any way I can make adjustments (in this case painting/selecting) the second layer and have it linked to the first layer so I don't have to paint/select both layers individually? Right now when I want to include more selection area I have to repaint the selection on both the colour and the hue/sat layer masks.