I think i can help. But to be honest, I felt like Darvus not doing anything was good enough, given that he has a reputation for being sullen and pessimistic.
Just play it cool with Nebel's actions. Its how Isparians say hello.
Oooh, uh...oh shucks! Us wacky foreigners! :D
~_~;
The prince is kinda an obvious duck... Rhayven's been in service to the crown for 15 years, much of that time he has made his home in south haven, not noticing the prince might be the princes preference, but it also doesnt make explicit sense for Rhayven, unless the prince has made a concerted effort to disguise himself.
Crud, I forgot to describe the council chamber. It's past midnight though, so I'll tackle that Wednesday night. In the meantime, I suggest the player characters take this opportunity to introduce themselves to one another during the pre-meeting period.