Strange behavior with Color Fills when combining multiple vector paths

There's something strange happening when I combine vector paths in Fireworks 8.  I'm building a logo that incorporates a globe, and I'm tracing the continents with the Vector Path tool.  Several paths were needed, and I combined the paths.  Then, I tried to fill the completed land mass with color, and I got very strange behavior (see the attached file).  

Instead of filling correctly, the color fills seemed to follow the lines between endpoints of the paths.  How can I get a true fill between composite paths?
strangefill.png