Using Bittornado and lost 4.0 GB of downloaded pieces. T_T

This is really sad. Please help me T__T

I'm on 256/128 ADSL. What just happened is . . .

I'm using Bittornado 0.3.1

1. I'm downloading a torrent that contains 26 files. The torrent have reached 80 % completed.

2. I use priority system. Set first 5 files(basically 5 episodes of the anime) to "download first". and other files to "download never". I let the torrent opened all night.

3. I woke up and saw the first 5 files finished. I set other files to "download normally" and close the torrent. (At this point i'm not sure if I 'set the priority back to normal before closing it' or 'close the torrent first then set the priority back to normal while resuming it')

4. Now the torrent is running with first 5 files completed but I don't see any cmpletion percentage of other files(which should be around 80%). So I close the torrent then open it again. The program performs the check for existing files. When it finish checking, it display current completed percentage at around 20%!! Which means the program is telling me that the only things completed are those 5 files. The rest were gone. T__T

This torrent contain a folder which is 5.67 GB in size. But when I right-click on the downloaded folder in my harddrive, it display the size = 5.07 GB. So I believe the data is actually not lost yet. It just not recognize by Bittornado's check.

Experts please tell me how to resume from that 80% I completed?

Thank you so much. sigh T_T