Do you have the settings for Projects to show only Available actions? There's a bug where actions inside an action group do not appear in the project view because the action group itself is not treated as available until all of its actions are completed. Because the action group isn't treated as available, it isn't shown if you are only showing Available actions. You might want to look at this other thread:
http://forums.omnigroup.com/showthread.php?t=16670
and send in a bug report with Send Feedback to request that this be changed.