Is there any to disable all block breaks by Magic?
There are some issues when broking the block and placing a block by player instead.
How to disable block breaks globally in Magic?

That exploit was fixed in the last release, I suggest you try updating to 7.6.18 before doing something so drastic. This plugin's default survival configs won't work well if you turn off all block breaking.

In materials.yml you can modify the indestructible list. Here's the default:

https://github.com/elBukkit/MagicPlugin/blob/master/Magic/src/main/resources/defaults/materials/indestructible.yml

There's no way to modify this per-world, so probably you should just disable wands or spells in those worlds with worldguard flags or permissions.

I still need a world setting to disable block breaks for some special worlds.