I'd check the return value...?
I notice you don't do that much.
Not critiquing, merely saying I see no overt flow control bug,
but reading the api notes the call only says it attempts to send,
not that it guarentees it. Since it sends when you wait by a yield method,
probably not the call per se, just putting in the good word for return value checks.
You might try bulletproofing calls with checks on the seedling count before
sending, or sending the seedlings the census count returns as a more robust
technique to the unexpected.
Again, I don't know lua / eufloria well yet, but we woudln't want players able to
monkeywrench cheat our hard levels by nicking 1 seed off a 1000 seed count
world and shortcircuiting a wave from launching. :-) Not sure if it would work
that way, and tangent to your thread, merely chatting.