Great tutorial--one of the best I have seen on the subject.
In my button, I added to minor tweaks to help sell the 'glass' effect:
(1) I moved the white overlay down and to the left 3 pixels in each direction. That leaves a dark blue border across the top of the button to represent its top side.
(2) If you look closely at the Microsoft glass buttons, you can see a white highlight running along the top of the button. To reproduce this highlight, I drew a white outline rounded rectangle, the same size as the button rectangle, on a separate layer. I cut the rectangle at its left edge, just before it begins to curve down, and at its top right edge, just after it finishes its curve downward. That leaves a straight line at the top of the button with a curve on its right side.
I moved this line down and to the left three pixels, so it sits over the edge of the white overlay. Now all I need to do is fade the highlight in from the left, and fade it out as it rounds the curve on the right.
To do that, I selected the line from its left edge to about three quarters of the way to its right side. Then, using the gradient plug-in for Paint.NET, I created a gradient from 100% transparent to 100% white and applied it to the line. That makes the highlight fade in from the left. I did the same thing to fade the highlight out as it rounds the curve on its right side. The result is a button that is nearly a dead ringer for the Microsoft button.
Thanks again for the great tutorial! I've wanted to do glass buttons for ages, but could never find a good recipe.
