Create a list/featureclass of unique values (with a total count) of a point attribute for each polygon those points overlay.

If you've created a list on the polygons you can use a ListHistogrammer to get those unique values and their counts.

Apologies, I need to get unique values of an attribute from the point layer, not the polygon, but write out the point attributes for each polygon. If that makes sense?

Not really. Do you want a list of unique point attribute values and their counts per polygon? Or the other way around?

Yes, the first.

Okay, so if you let the PointOnAreaOverlayer generate a list on the polygons and then run that list through the ListHistogrammer you'll get a (sorted) list of unique values for the list attribute you picked and the number of times they occur.

Thanks for the suggestion, but it didn't work... it says no list attributes available. My workbench looks like this.... I really appreciate your help.

The ListExploder is because the polygons overlap in places and so points can be in 1-3 polygons, and I wanted to write the point to each polygon that it falls in.