Photoshop CS 5
Thank you for super lesson. Actions as you say seem to be quite addictive! I have played for hours.
The link I found most useful (I discovered others have found it useful as well) is:
I have downloaded few actions from there.
Here I have combined Watercolour action with your Double Stroke Action:
Venice water colour & double stroke.
Unfortunately it does not show border well due to white background!