The Mercury add-on is not compatible with Orbiter2010, so it won't work.
For the Apollo, it may depend on what version you have. First, do you have AMSO or NASSP? Second, have you checked if the version of your Apollo add-on is up to date? The current AMSO is 1.21. It seems that the current NASSP is 7.0. If you have an earlier version, it may not be compatible with Orbiter2010.
Finally, if everything should be O.K., but it still doesn't work, could you post the content in your Orbiter.log? (found in your Orbiter root directory)