Generated blocks can't spawn structures.

Hi, i want help to spawn structures parts, because structure is huge :)

Structure parts can't spawn with block procedure "When block added" etc.

I created block that when block is generated/placed, will spawns structure parts.

I used any way but not work.

I used "Ore Generation" for block but didn't spawns structures, and i used structure 1x1x1 for block(SpawnerStructure) but also didn't work. There is another way?