The following steps will resolve this issue:

1. Download and install SOHO Notes 5.5.2.

2. Launch the OpenBase Manager application (/Applications/OpenBase/).

3. Click the Local button and then select the Chronos_yourusername database in the list. 

4. Choose Action > Stop Database and then Action > Delete Database.

5. Launch SOHO Notes. This will create a new database.

6. Choose File > Restore Database > From a File. 

7. In the Open dialog window navigate to the following directory on your computer:

~/Library/Application Support/Chronos/Previous Version Backups/

Where '~' denotes your home folder.

8. In the above directory select the most recent backup file and click Open. 

This will restore your StickyBrain 3.x database.