Direwolf20 (1.6.4) 1.0.5 update removed my save

[RouteMaster]

Hey FTB~
Last night I was playing on my world which I made on the 1.0.2 update, I had updated it every time a newer one was available until I tried updating it to 1.0.5 this morning, which as soon as I did my world was removed from the single-player screen.. But the strange thing is - The world save is still in my FTB save folder, BUT the folder size is only 6mb

~ I have another world(145mb) which I made in 1.0.1 update and that works perfectly in 1.0.5, I checked between both world saves and it seems the region had been deleted by the 1.0.5 update in my new world. Is there anyway to recover the region files or even .MCA files? ive already done a full harddrive scan for any lost/deleted files but I couldn't find any trace of them or .MCA files
OHH another thing, im still able to open the level.dat in MCedit, although all my buildings/everything is gone which just makes it a new world with the same seed.
thanks for any help posted

 

[UniZero]

If the files are then I am afraid it is most likely lost. Make a new world.

 

[Ashzification]

Prior to any update, always back up your saves to a different folder.
Example: This is the file path for my world save C:\Users\Adam\Desktop\FTBLauncher\MagicFarm2\minecraft\saves\Let's Die a LOT
Before I updated, I moved the contents of that folder to C:\Users\Adam\Desktop\Modpacks Backup\MagicFarm2\minecraft\saves\Let's Die a LOT
I moved my entire mod pack folder to my back up location. That way, if there's a problem with the pack update, I have the exact setup available to continue playing my world