March 4th, 2011
When adding time, you may get double references in the table under the calendar. This is just a display bug and closing the app and re-opening will set the tables up properly. If you try to delete a doubled row, the application will crash.
A fix in a new version 1.6.1 has been sent for review by Apple.
Thanks Russ M!
Update: 1.6.1 has been approved by Apple. Please backup your data before updating! Sorry for the version churn.