Configuration for Tree Component

[simplesi]

Hi -

Your PCF controls look absolutely excellent - I'd really like to use them in our project.
However, I'm having trouble configuring the Tree Component:

I get an error message in the javascript console when viewing a form with the component configured:
An error occured starting up the pcf TypeError: Cannot read properties of undefined (reading 'sort')

Here are the fields I have configured:

All other fields are empty.

The relationship between the two tables is:

The relevant fields from the tag entity are:

The documentation seems to suggest that Tree Entity Collection Name should be "Plural name of the related entity", and the control configuration in Dynamics says it should be "The logical name of the collection of the tree entity". Assuming this means the name of the entity containing the tree elements, then this should be what I've listed. Or have I misunderstood?

It would be amazing if you could point me in the right direction to get this working.

Thanks,
Simon