I recommend ignoring the calendar datamodel, use the acs-events service if it does what you need, but I just recommend using a simler data model specific to your application.
Then I recommend using the ADPs from calendar to display the data in a calendar format. If you generate a multirow with the right data it should work.
Alternatively you can fork temporarily, and when the new package object types work is done this summer, you could subtype the calendar package.
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