Nexus One - how to upgrade to CyanogenMod-5 [stable 5.0.6 version of 04/15/2010] - detailled instructions

I just upgraded my Nexus One to CyanogenMod-5: Kang Central Station (STABLE) [04/15/2010 / 5.0.6].

As it is just a CyanogenMod-5 upgrade from 5.0.5.3-N1 to 5.0.6-N1, only the following steps are required :

1. download the Cyanogen 5.0.6-N1 (the latest stable CyanogenMod for the Nexus One) from Cyanogenmod For Nexus One V5.0.6 (04/15/2010) : update-cm-5.0.6-N1-signed.zip
2. check the MD5 sum :
   md5 update-cm-5.0.6-N1-signed.zip
   and check the checksum
   MD5 (update-cm-5.0.6-N1-signed.zip) = 43835d679958294befa16af78bf7311b
   against the one of the forum MD5Sum: 43835d679958294befa16af78bf7311b
3. connect the Nexus One to the computer and mount the Nexus One in the Mac
4. copy the Cyanogen 5.0.6-N1 (the update-cm-5.0.6-N1-signed.zip) file to the root of the Nexus One SD-card. Wait a few seconds in order to be sure everything is copied to the SDcard. Unmount the Nexus One on your computer.
5. Reboot the Nexus One in bootloader mode : hold down the trackball while you press the power button. Ensure to maintain the trackball hold down until the screens turns to a white screen with 3 green android skating at the bottom of the screen. Ensure that the Nexus One stay connected to the computer via the USB cable.
6. on the screen, the BOOTLOADER should be highlighted with blue. press power button
7. on the new screen, scroll down with the Volume down button to highlight the RECOVERY option. Press the power button.
8. the Nexus One reboots and after a few seconds, the screen title with "Android system recovery" appears, with the "Build : RA-nexus-v1.7.0" at the bottom of the screen. The screen should be in cyan instead of green if the Nexus One has already been rooted
9. scroll down with the trackball to the "Backup/Restore" menu and press the trackball
10. on the new screen "Choose backup/restore item" choose the option "Nand Backup" (the first one) by scrolling down the trackball and press the trackball to select it. The question "Create Nandroid backup?" appears at the bottom of the screen, so press the trackball to confirm as it is stated
11. The backup starts, it takes a few seconds to complete. At the end of the backup, the cyan screen is restored. Press Volume down button to return to the previous screen "Android system recovery".
12. FIRST INSTALL ONLY : scroll down to the "Wipe" item using the trackball and press the trackball to select the option
13. FIRST INSTALL ONLY : in the new screen "Choose wipe item", using the trackball, select every wipe item one after the other and perform the wipe pressing the trackball. When every wipe has been performed, return the the previous screen using Volume Down button.
14. back to the Android system recovery screen, scroll down to the Flash zip from sdcard item using the trackball. Press the trackball to select
15. on the new screen "Choose update ZIP file", use the trackball to select the right ZIP file to flash. Here, there should be only one zip file available to flash : update-cm-5.0.6-N1-signed.zip. then press the trackball to start the flashing. Press the trackball again to confirm flashing on the question "Install : update-cm-5.0.6-N1-signed.zip ?" that appears at the bottom of the screen. The ROM flashing starts and many messages appears on the screen.
16. after some time, the message "Install from sdcard complete" appears and you're back to the cyan screen "Android system recovery" with the item "Reboot system now" selected by default
17. just select the default option by pressing the trackball down. The Nexus One reboots.
18. after the Nexus One has boot the normal way, just to be sure, check the "Mod version" value in the "Setting" then "About Phone" : the value should be "CyanogenMod-5.0.6-N1"

I adapted the instructions from Step by Step Guide on How to Install Cyanogen Mod ROM on your Nexus One! to perform the upgrade.