It depends. If you're playing a multi-round stroke play event, the event format has to stay the same for each round.
If you're playing a multi-round match play event, like the Ryder Cup, you can change the format for each round.
The reason for this is PlayThru needs to build and sort the live leaderboard round a score. If you are playing individual stroke play in round one and then 2-person best ball in round two, there is no way for PlayThru to sync those scores because Player 1 and 2 Person BB Team 1 are not the same golfer.
We can do it in a Match Play format because each team is assigned a Full Event Team Name (e.g., USA, Europe). In that case, each team wins points for their team and those team points are shown on the leaderboard.
The combined leaderboard aggregates each golfer's scores across both rounds.
For every round you add, you'll be given the chance to add or change the tees.
This gives you the freedom to play different courses each round.
Because each round may have a different roster of players or teams, you you can toggle between the rounds in the Golfers Tab.
The columns that show for that round will align with the Game Format set for that round in the Event Tab.
Changing scoring settings after Round 1 is marked "Complete" may affect accuracy (settings lock with a warning).