OK, I did finally get to the part of the game where, if I have the Expert interface enabled, it will tell me what the rules of the game are.
Two more questions/issues:
1) in terms of the weight (as changed by SHIELD), does that only have an effect on collisions? or does weight also play a role in the movement "momentum", e.g. if I SHIELD, I will slow down faster? the way I'm reading it, it's collisions only - since the slowdown is listed as a constant friction multiplier, but it's not 100% clear
2) this is probably more for arena game mechanics in general, but a weird thing happened to me: I wrote some code while in the Bronze league, submitted it (several times, actually, because I usually did not wait for all the combat pairs to play out until I wanted to iterate on the code), got confirmation that I was going to be "promoted" to Silver league in an hour or so, and went to sleep. When I woke up, I actually had notifications that I was promoted twice - apparently I beat Silver league with my Bronze league code!
Which is cool, but the downside of that is that I didn't get to practice the shield mechanic before having to deal with 4 ships on the screen.