Employee Central error on hiring

http://scn.sap.com/thread/3826217

Hi there!

This is somewhat related to the post in the above link. I'm hitting multiple errors in my DC8 demo instance while trying to hire some dummy employees:

1. Uploading of new employee's Job History file resulted in validation error in the upload process
2. Alternatively I tried to manually hire an employee, but encountered another error about wrong dates, similar to the error when we upload
3. When I tried to force the hire by moving to the Compensation tab... after clicking Save, a blank error pop out prevents anything from moving ahead:
   
4. On a side note, I also tried to upload the CSF Succession data model, exact same one which I just downloaded from my instance. Upon uploading, it shows that the USA country code is missing in the system
   
5. In the URL above , it was suggested that we switch off and turn on again EC v2. I did that but the above error persist.
   

Really appreciate if someone can enlighten me on what can be done to fix this.

Cheers!

TC