For the march/april thing it's a long standing glitch. CUrrent thought is that it has to do with daylight savings starting on march 31 and the iPad calendar app having a hard time figuring out exactly when april 1 starts since, for some, the 31st is 23 hours, for others 24 hours.
If you have any all day events on April 1st, holidays, birthdays, subscribed calendars, edit them to be a few hours long instead of all day and the crashing should be resolved.
When the app can't figure out when the month ends it has a hard time figuring out when an all day event starts, so it crashes.
As to the other thing, I'm not sure.