i don't know what happened but seems like the episodes are now in. I just went and check on the series again but somehow the episodes that was not there is there now. I am not sure what happened. Cause I did re-open pvd a few times during when there is problem. Seems like working now.
I just tried importing another TV series from imdb and after import, I need to press the save button (green check button) and the episodes will appear.