oneblock map unable to regenerate the blocks

Put the summary of the bug you're having here

What I expected to happen was...:
nre blocks are genetaraed when break invisible block

What actually happened was...:
when break the oneblock it becomes invisible and un minable 

Steps to Reproduce:
1 download the onebalock map from OneBlock Minecraft Map (planetminecraft.com)
2. place the downloaded folder in Minecraft saves folder 
3. launch the  one block map and break the block