If you want to go back to the state before the upgrade,
01. Take a cold backup of db before upgrade.
02. Perform upgrade to 188.8.131.52
03. After a day you decide to downgrade to old version and are ok to lose the changes done since upgrade, then restore the from backup taken in step 1 and start the database using old home.
If you are not willing to lose data then follow the link you have posted to perform downgrade.