Well, after a lot of thought and work, I think I have finally come as close to an 'Arrest' scenario as I can get. It meant I had to tile another new map, but I'm actually quite happy the way it worked out.
OK, so now when you surrender
You are basically forced to turn yourself into the police headquarters (or else the Police force will attack you if you don't)
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Where you are stripped of your inventory and squad
and detained for a while...
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Instead of turning off all the Locations and forcing the player to the transport mission (formerly the police HQ/arraignment mission) like you suggested, I decided to allow the player to choose to rondevous with Prison transport or to not go there, there by effecting an 'escape' attempt.
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I figured that if the player chooses to try and escape (not go to the prison transport/train station) that this would give as good a reason as any to enable some 'Bounty Hunter' random encounters, and using some CVARS to script a few fugitive type situations in some of the closer locations (to South Lake City).
If the player does choose to accept his sentence and actually enters the Prison transport mission, then he is 'processed'
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and transported to the actual Prison Mission via the 'GOTO_MISSION' command
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Req, thanks for all the valuable insights, without your help, I probably wouldnt have been able to finish. It will be alot easier to use duplicate maps of the 'Prison transport' mission than re-scripting and duplicating South Lake City. Thanks again.
As a bonus, it turned out that having a vehicle on the map worked quite well, as the Arresting officers always seem to find the car a lot faster than when the squad is on foot. In fact when the player 'parks' the car and commits a crime the arresting officer will often come accross the parked vehicle and begin to smash it (using only a melee attack) making the player choose to come back and defend it, or else the police will destroy it. (and nobody wants to lose a vehicle.) Once the player 'surrenders' they will stop attacking the vehicle.
Now I'm wondering what can or cannot be done with vehicles and tagnames...