CustomerInfo nickname and reference_id usage in different platforms

Question

I find that the nickname and reference_id fields work differently across platforms and I'd like to get clarification on how they should be used.

1. With the API, I can retrieve and set both these fields.
2. In the web-based dashboard, both fields are displayed and can be edited if present, but there's no way to enter a nickname when creating a new customer.
3. In the Register iOS app, none of these fields are shown or editable. They're also absent when creating a new customer.

What I want to do is map Square Customers to our existing members, but we're facing three problems:

1. reference_id seems to map perfectly with our existing member numbers but, as mentioned, it's nowhere to be seen in the Register app.
2. Searching customers in the Register app only searches in names and emails. It would really help us if it searched in reference_id as well.
3. CustomerGroupInfo is read-only via the API (and not even an endpoint). We would map these to our membership levels.

As of now, I'm looking at ugly workarounds, but I wanted to know if something in the roadmap could help us out. Thanks in advance to the people at Square!