The way foregrounds are drawn in relation to backgrounds was changed, for the worse in my opinion, for OD1.20
In fact, it broke my favorite dock. I wrote a bit about it here: http://www.feebdack.com/article.php?id_art=10
The "Foreground Example" dock background itself has not changed, rather how foregrounds are drawn was changed somehow. If you apply the Foreground Example to a dock and do not see the foreground, try increasing the size (Appearance -> Icon Size Slider). You'll see what I mean.
Sorry I cannot offer "help or tips", only sympathy.
