How are the ignore flags supposed to work?

At the moment, when using a raceconfig.xml file in a mod directory, the following things happen:

1. The race doesn't appear in the "Pick Your Civilization" screen. This would be the main point of the ignore flag and it works great.

2. The race does appear in the "Choose Opponents" screen. Not sure if this is intended as you can add custom races via other xml files but it's no show stopper.

3. On the same "Choose Opponents" screen, after adding a custom race it cannot be removed. That is, normal races work fine but any ignored races can only be added and not removed. This IS a problem.