Builder's Boots MOD (Final Update!)

This is my first mod! Please write comment of points to be improved!

This mod adds boots that can place scaffolds.
Because of something, I cannot add pictures in description. 
First,"Builder's boots"
This boots place scaffolds under you. When you sneak,they break scaffold under you. So you can go down.
They needs the next scaffolds.
Second,"Scaffold"
It will break and return to player after about 10 sec. 
Third,"Creative boots"
It has no recipe for crafting.Only creative mode.
It does not need any scaffolds.
Creative scaffold is a replaceable block,so you can set block at the same position.
<In-game language support>
English,Japanese
<About Workspace data>
I hand out you my workspace data because I want you to understand about procedure system and create awesome mods with MCreator.
Please download it and use free.

Caution! Do not use both of boots at position X=-0 or Y=-0.
May be this is a bug,but I cannot fix it because "-0" is a number that cannot be specified.