No biggie, but thought I'd post this just in case it might help someone.
I posted the original of this some time back, but never was really happy with the waterfall. Just didn't seem complete.
Well, today I happened upon it, and decided to see what I could do. What I did, was to use the chalk tool at low setting pressure, wide settings. It did a pretty good job of giving me the "mist" effect I wanted to go along with what I already had.
The first painting is the original, the second, the one I touched up today.
Hope somebody finds this useful.