If you are playing a matched play game, you are allowed to have an understrength unit in an Auxiliary Support Detachment. Due to constraints within Battlescribe, we are not able to reflect this in the error checking. To properly calculate your PL and Points, add the unit you want to take as an understrength unit and then open the context menu on each model in the unit you do not want to use via right click or tap and hold. Then delete the model from that context menu. This will permanently display an error in your list, but it will calculate your points correctly.
Instead of following the normal rules for Rapid Fire weapons, models in this unit shooting Rapid Fire bolt weapons make double the number of attacks if any of the following apply - The shooting model's target is within half the weapon's range - The shooting model is Infantry (excluding Centurion models) and it's unit Remained Stationary in your previous Movement Phase. - The shooting model is a Terminator or Biker For the purposes of this ability, a Rapid Fire bolt weapon is any bolt weapon (see page 195) with the Rapid Fire type.