Sprint: You can rename your Sprint by clicking on it.
Sprint Interval: You can define your Sprint Interval by selecting the start/end date.
Members: You can add part time members of your project (e.g.: you have 5 developers working full time, one working half time, members should be 5.5.).
Days: You can define working days in your projects.
Personal holidays: Note to put sum days here, the cumulated number of all the days of all your dev team took off during a sprint.
Bank holidays: Note to add the number of holidays only (official holidays as christmas, easter, etc.) and DO NOT multiply this number with the number of your team members.