I understand what you are seeking to achieve. In part, it can be done with the current plugin.

Before you select a county, all towns would show, but as soon as you select a county, only towns in that county would show (as an example). If you are happy with this, then ….

In the General Settings, make sure the two Auto Count settings are ON (by default they are off).

In the form UI fields for County and Town, make sure Hide Empty is on.

Further options and flexibility will arrive in the next major release (V3), which we are working on right now, but is yet some months away.

The links, if one can call them that, are made in the posts. When you select a Country and a Town in a post, our cache then assumes that town belongs (not always/necessarily exclusively) to that Country. That does rely on your user getting it right in the posts.