In scenes where the spotlight player does not set the stakes at the outset, do players declare for or against him beforehand?  I'm having a hard time digesting when people choose up sides generally.  Seems like some players will want to see which way the wind is blowing before they declare, particularly when there are roached characters involved.

As soon as stakes are set, people need to declare which side they are on.  So if it isn't immediately apparent what the conflict is about, players can wait to see what develops.  In practice, dog-piling isn't uncommon, particularly to gang up on someone with a high reputation. 

Welcome, by the way!  I hope that answers your question. 

Thanks.  I'm teaching/moderating it later this month and really want it to go well.  A couple of the players don't have access to the rules - trying to make sure I've got the rules down.