Item Storage doesn't work

So hearing about lapis and enchanting in the new update, I switched from 1.7.10 to 14w19b. This was a LAN server, keep in mind. It was also survival. So anyways, I switch to the new version. It's laggy, but okay. After seeing the lag though, I enchanted my stuff and switched back to 1.7.10, only to find that my inventory had emptied. My chests were okay though. I switched back to the snapshot to see if it saved in the other version, and it didn't. When I switched back to 1.7.10, my chests had also emptied. Attached is my save file.