It's a project that adds new blocks and items to the game. Soon, it'll add new mobs,but for now it's just blocks and items. So far it's 23 new blocks and 15 new items, 4 of which are replacing existing items. Some blocks have kind of advanced functionality, like emulating the nether reactor from MC:PE and giving items custom tags to change how they behave.
Over-engineering may be the problem, as I am not at all a command expert, hence this call. My commands are also not very organised so that adds to the possibility