Unfortunately, some good stuff from the old site couldn't be brought over to this new site. But some you can easily restore.

Old forum post attachments: all left behind. so if you see old posts that refer to an invisible reference, you know what happened.

Old avatars: gone, buy you can easily replace them now at your profile page.

Forum signatures: though not exactly gone but we now use different formatting here so you might have to retouch your forum signature.

Post here if you see any other stuff missing. We might be able to do something about it.