I had a look at the code and it looks like this:
//Setup Child Page - Main View/Activity
TabInfo tab = CreatePage(PortalSettings.ActiveTab, PortalId, TabId, "Group Activity", false);
//Add Module to Child Page
int groupViewModuleId = AddModule(tab, PortalId, "Social Groups", "ContentPane");
int journalModuleId = AddModule(tab, PortalId, "Journal", "ContentPane");
int consoleId = AddModule(tab, PortalId, "Console", "RightPane");
ModuleInfo groupConsoleModule = ModuleController.Instance.GetModule(consoleId, tab.TabID, false);
TabInfo memberTab = CreatePage(PortalSettings.ActiveTab, PortalId, tab.TabID, "Members", true);
ModuleController.Instance.CopyModule(groupConsoleModule, memberTab, "RightPane", true);
As we can see a few things happen before the failed CopyModule - however the first thing that stands out to me is that the Console module is added to "RightPane" - this seems wrong to me as the only mandatory pane is "ContentPane" (RightPane is there by default as it's in our default skin and template)- so if your skin did not have a RightPane module that would fail, then the consoleid would be 0 and that could cause groupConsoleModule to be null and the CopyModule to fail. I would check your skin first, and if it doesn't have a "RightPane" then please add one as it seems it's a requirement for the use of that module (or at least automatic setup)