https://pastebin.com/zdF26uFW

Using the above config, I was unable to hammer stone, cobblestone, or grass in Creative mode. After changing the creative value harvestLevelBlock to -1, I was able to once again hammer stone and grass in Creative Mode (but oddly enough, I could not hammer a block from A Little Extra Tiles, Borderless Brick Grout, even with that setting applied).

Seems limitAffectedBlocks isn't being applied when in Creative mode.

I should note that hammering this same block DOES work in survival with the above settings.

The setting that is causing this behavior is "editUnbreakable" in the Creative section.

Delete your config file and download the newest version. I messed up the difficult configuration.