Here are the questions so far:
Q: In the Accuracy thing, are we allowed to shoot sequentially, or do we all have to shoot at the same time?

A: One person shoots at a time. You can choose what order to go in. But each person needs to finish before another can start.

Q: Do multiple flaming spheres in the same square stack? (Test of Power)

A: Yes

Q: Is there a penalty to casting while doing this? (Test of Balance)

A: Yes, you have to make a concentration check equal to the DC check.

Q: Would feather fall do anything in terms of causing other people to fall or avoiding that? (Test of Balance)

A: All it would do is cause the person not to be able to make a tumble check, so I wouldn't advise it.

Q: What does the thing about having init higher than 25 mean? (Test of Teamwork/Quickness)

A: Let's say someone goes on init 28. Let's also say that there is a target that pops at increment 20. This would correspond to round 1, init 5. Let's say that it lasts 15 increments. This means it will last until round 2, init 15. In reality it lasts 3 extra increments (18 instead of 15), but the test is normalized to 25 increments per round.

Does that make sense? It doesn't from a realism standpoint, but it just makes my life easier from a mechanics standpoint.

Similarly, though, it means that if none of you manage to roll to init 25, you'll actually be losing increments. I'd recommend not allowing that to happen if possible.

Q: (OK, well it's more of a comment, but I have an answer to it) I kind of suck at game lore. (Test of Knowledge)

A: Only a few of the questions would you be able to discern from game lore. Most of them will call for various checks. As a note, they won't all be just knowledge related checks.

Q: How big is the arena? Do the targets appear at random or is it set ahead of time? are there walls within the 30' center (red target zone) Does only one target appear at a time? (Test of Teamwork/Quickness)

A: No one can tell you exactly how big the arena yet or how the walls are lined up yet. The best info you can get is that it large (possibly 100' or even bigger?) and that the walls are mostly L shaped and split the arena into multiple sections. The targets will be set via a script that I write but will be random. OOC: for planing purposes I will also tell you that there are no walls within the red target zone. Also, I will be enforcing a 20 seconds for your turn on this event. If you don't act within 20 seconds, your turn will be skipped.

Q: Can they be sneak attacked? Can they be tripped? (Test of Power)

A: Nope and nope.