I finally figured out what the problem was. I had environment filters on my features that were causing the problem. For example, all of my features had the en_US language filter set and I did not have any language filter specified in my configuration pom in my list of environments under target-platform-configuration.
So, once I removed all those filters, I was all set.
However, now I have a closely related, but different problem. A few of my features have native libraries in them and so they have the appropriate environment filter set on the feature. However, I believe that when it goes to build the product for each environment configuration, it tries to include every feature specified in the product definition. But, the Windows configuration should not try to include the MacOSX feature because the filter is causing it to fail in finding it. Of course, I don't want to include MacOSX features with a Windows product build.
I've looked on the web for a solution and found a bug from 2011 that seems to talk about this problem but had no resolution. Surely this is something people have to deal with. What is the right solution? Is there a way to specify some product features as optional and when it doesn't find it, it doesn't include it?