Is it the case thta FGs can be formed among any number of adjacent GO units, regardless of their firing status? That is, a fresh unit can join in a FG with a group that has a FIRST FIRE counter along with a unit that has a FINAL FIRE counter on it as well? The fresh unit would contribute its full FP and the other two half of their FPs each.
For the FINAL FIRE unit to join the FG, the enemy unit would have to be adjacent to it. So that unit's FP would be doubled. The other two units may have their FP doubled as well if the enemy unit were adjacent to them as well.
Is this all correct? I think so.
PS: I'm starting to see why this game is so addictive!