[magick-users] Replacing a color always returns black for the "new" color

[Bill Ten Broeck]

I am trying to take an image I have that has only 3 discrete colors, and 
change them to a different color. I also need to add transparency. I'm 
new to ImageMagick and am following the instructions at 
http://www.imagemagick.org/Usage/color/#replace_draw

The original file format I receive is gif, and I'm trying to end up with 
a transparent PNG. My first step is to run the following:

convert test.gif -matte -transparent "#000000" test2.png

This works - no problem. However, when I then try to change one of the 
colors using the above web page for examples, I end up with the new 
color ALWAYS being black.

An example of what I have tried is:

convert test2.png -opaque #0000ff -fill #1e731e test3.png

I know it is finding the color with the opaque definition, because it 
always replaces that color area, without fail, with black. 
Unfortunately, that's not the color I need it to be replaced with :(

I have tried numerous input file types (created with Photoshop) and 
multiple syntax variations, but the results are always the same... the 
new color is black.

I know this has to be a basic error on my part, but I have not been able 
to turn anything up. Could someone possibly shed some light?

Thanks.