That's interesting. Depending on the number of tracks/artists that you initially import it is possible that the tool won't find any similar artists.
Can I ask how many tracks and artists you are importing from your playlists and how many artists you are selecting in the parameters panel?
I was importing a few hundred tracks with many artists. But I wasn’t selecting any in the drop down menu. Perhaps make that optional to select all? That’s what I thought it would do. Thanks for the cool tool!