Force Re-run set up assistant in Yosemite

Good morning

I have had a hard time to migrate the content of my Mac Book Pro (end 2011 and with last version Yosemite 10.10.3) to my new iMac (same OS)

Nothing worked.

I had run the set up assistant completely before doing the migration and it was really a bad idea although Apple says it is ok to do so.

No way through my external drive with Time Machine Back up of the Mac Book Pro

No way through direct connexion between both computers through Thunderbolt cable

All the time the process get stuck and dead at the end, at the level of indexing the files.

1/ I tried to solve the first problem : with an encrypted source computer (and of course encrypted time machine back up) it is not possible to migrate on a Mac that have already a user so I decrypted the Mac Book Pro and did the Time machine Back up again on it. No success either trough the new time machine back up or direct thunderbolt connection between the two computers

2 The problem seen in the console seems to be the UID of the user. But I had, as asked, changed the name of the new user = No way. It get stuck at 8 minutes to the end.

There is no hidden other user in the Library. And I had only one user in the old Mac Book as in the iMac.

As I get a little tired (Apple care is desperately unprofessional) with all that I want to try the solution proposed here :

http://www.engadget.com/2014/08/23/how-to-make-os-x-mavericks-re-run-the-setup-a ssistant/

1. Boot into single-user mode by holding down Command-S on the keyboard during startup
2. At the command-line prompt, type

   mount -uw /

3. rm -R /Library/Preferences

4. rm -R /Users/YOURUSERNAME/

   <-- replace YOURUSERNAME with whatever your user name is

5. cd /var/db/dslocal/nodes/Default

6. ls

   (to list the files)
7. Delete the file that is named after your user account with a

   .plist

   extension. For example, for user name "stevesande" you'd type

   rm stevesande.plist

8. rm /private/var/db/.AppleSetupDone

9. reboot

But as it is a solution for Mavericks I am not sure it would work on Yosemite

I had already tried this solution:

http://www.theinstructional.com/guides/how-to-re-run-the-os-x-setup-assistant

The following command will check the filesystem to ensure there are no problems. Enter:

/sbin/fsck -fy

The next command will then mount the filesystem for it to be accessible:

/sbin/mount -uw /

With the filesystem mounted and accessible, it's time to remove the file so OS X will re-run Setup Assistant:

rm /var/db/.AppleSetupDone

It didn't work either, as the last line of command proposed give back the answer "no such file" or "file doesn't exist"

So I was unable to delete the non existing .AppleSetupDone file

Before re-installing OS X Yosemite from the Internet, I liked to know if anybody as a solution to force the set up assistant of the iMac (which would erase the user I set up at the beginning and start with no user at all)

Thanks for your help

Constance