Currently CalendarPlant is free!! When you launch CalendarPlant you will find
in the status bar indicating you have an active subscription.
If one of the CalendarPlant editors has insufficient data, then and error indicator will appear in the info bar until the required data is specified.
You can actually add a time frame by only give it a name, but this is not enough information for generating anything in the Google calendar. If you have done this you will get a warning status indicating that you have specified time frames that will be ignored. This warning symbol will also appear next to any such time frames in the Master Planer.