Hi, you may have a look at:
It helped me start. There are maps in the content of the plugin, with samples. But I wonder if the samples are there as an exemple or for the algo to determine the authorized neighbours.
However, as said in the post: Instantiate the WFC editor widget. Then, use it in a map: set the size, samples, and press collapse. The result will be spawn at 0,0,0 (for me). Anyway, use the outliner to find it in case. Start small. My PC is trash, and was on its kness quickly with bigger structures. WFC is a np algorithm if I understood it well, so it can become crazy expensive really quick ^^
Hope it helps