Unlock the level

Hi,
I found a blueprint about the level unlocking system on the forum Level unlocking - World Creation - Unreal Engine Forums
But I don’t really want it to be a widget, for me it’s a level with actors, each actor corresponds to one level, can someone help me transform it?

  • I would like the actor to turn green after unlocking

Each cube is like this:

In the level BP ( main level BP ):