Yes, it's in another thread.... somewhere. You rename the family files in the library folder, or move them to a backup folder. I did this, and my game created a new bunch of families. I had raptured all the premade families first.
I have the doppelgangers, too, and I wish there was some way to separate my created sims from the pool.
Getting rid of the dopplegangers is easy enough with AwesomeMod. The trick I'm trying to learn now is how to prevent them from happening at all. I'm pretty sure the
Exports folder is okay and the .sims3packs in there can be left alone, and controlling what's in the
Exports folder is useful as genetic seed stock for the new genetic immigration feature of Indie Stone Mod. Very cool idea.
I'm also pretty sure that the
SavedSims folder is the vaunted "sim bin" but am checking here to see if someone in the know can confirm before I go mucking around with it. I'm also not sure whether the files in there are indexed and need to be deleted from within the "Premade Sims" section of CAS, or whether it's safe to just delete the .sim files directly from the folder itself.
What I'm not sure about is whether any of the households created in CAS (or installed from a .sims3pack) in the
Library folder have any effect on the immigration pool or not. For example, if I leave the Reapers household (all the sims from Dead Like Me) sitting in the
Library folder, will the game eventually immigrate a new household using all the sims from the Reapers household sitting in the Library? If so, I want to delete such households from my game too. Although I am pretty sure that the only safe way to delete custom households like this is via the Edit Town UI.
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Okay so to delete a doppleganger that does make into your town, you need AwesomeMod running and you need a house that is cheap enough for the doppleganger to afford moving into if it's currently homeless. The trick is to get the doppleganger into a house all by itself, then use Edit Town mode to Evict that sim from the house, then click the sim in the Edit Town clipboard, then click the trashcan to delete it for good from the town.
The hard part is finding the doppleganger. It might be homeless (use AwsomeMod's "listhomeless" command to see whether this is the case). Or it might be the named owner of a household (look at all the household tags in Map view or Edit Town mode to see). Or it might be a roommate of an existing household with a different surname than the doppleganger, and in this case I think the only way to find out is to use Edit Town > Change Household to examine every household on the map.
Since AwesomeMod enables you to split a single person from a household regardless of their age, if it turns out that the doppleganger is a roomate of people that you don't want to evict too, then use Edit Town > Split to move the doppleganger into it's own cheapo starter home, and then you can Evict it from the starter household.