For the moment when enemy fires before unit surrender I suppose you'll to do something with the doFire command. Search in the forums. Then, for the unit's surrender, you have to put in the prisoner's init field : this setCaptive true (or in a script : prisonername setCaptive true) in order to avoid that the enemy shoots him (the prisoner). You also have several animations : FXStandSurUniv, or FXStandSurDown, or FXStandSur.
Hope it helps you
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