After 4 weeks of wait, I finally got my result: I passed!
General Considerations (maximum = 100): 99
Documentation (maximum = 70): 70
O-O Design (maximum = 30): 30
GUI (maximum = 40): 31
Locking (maximum = 80): 44
Data store (maximum = 40): 40
Network server (maximum = 40): 40
I lost points only on GUI and locking. I used the socket approach, and also an implementation of the model-view-controller pattern.
I implemented in GUI the option to delete the selected record. So, I suggest all to do not do this.
I do not know what happened in my locking strategy. I tested it using JUnit and several test cases.
Well... It's done!
Good luck to you, ranchers!