Tell your friend to re-install the game, and never never to move pre-made sims to other hoods, as they are.
You have 4 neibourhoods, and each hood sim has a user number, and a sign in which hood he belongs. Thus, General Grunt will be signed N002_user 36, and Mortimer - N001_user 1. When moving them as they are, the simulator "wants" to go to the original hood (N001, 2,3,4), and searches for the "signed sim numbers", doesn't find it there, and - crash is imminent.
As Ancienth said, there is a possibility to package the lot, and then install it in a new custom neighbourhood. Thus the family members will be with different user numbers, no memories, and no friends - just as any regular downloaded house lot with a family inside.
The procedure is:
1) Exit to the hood view, click once on the lot, and choose the asteriks (*) - "package lot to a file". The lot with the sims in it will be packaged, and the file can be found in the Packaged Lots folder (my documents/EA/TS2/Packaged lots). Do it to all your hood families.
2) Open a new neighbourhood. Exit the game.
3) Enter the folder Packaged lots, and install all the hood lots. You will find them in the house bin.
4) Enter the game again, pass to the new hood, and paste the lots. The sims inside don't have any connection with the pre-made sims, because they will get a number: N005 (6/7)_user 275...for instance.
5) Delete the lots in the house bin. Pass to the next hood, and make the same.
If you want to resurrect some sims before (for instance, the Dreamer's wife) - you have to do it before packaging the lot.
Edit: I clicked on the link you gave, but got a message that the thread is not found. So, copy and e-mail your friend my answer, if you want...

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