Yes you can manually install it, though I "thought" it should correct itself when you ran setup again. I'll have to look into that.
Just go to Administration Menu > Advanced Tools > Feature Installation/Configuration.
Verify that you don't already see it in the list of installed features. If not then click add new feature at the bottom
For Feature Name Resource Key put "FeatureName"
For Resource File put "STSEventCal"
For Control Source put "Events/EventModule.ascx"
For Feature Guid put "5a343d88-bce1-43d1-98ae-b42d77893e7b"
For sort order 500
For Default Cache 0
After saving it visit the setup page one more time to make sure it gets its module settings.
Hope it helps,