I have imported the england locations, its showing in admin as fine also with all of the cities.  However when you go into the listing you are unable to select past Citys starting with a C.

Confused how to repair

@Paul
Maybe there is limit (too many cities?).

I have the same problem in Germany, there are simply too many cities in the Bavaria region. The customer cannot choose anything. Is there already a solution for this?

There is hard limit on oc-includes/osclass/frm/form.form.class.php

  protected static function generic_select($name , $items , $fld_key , $fld_name , $default_item , $id, $limit = 2500) {

change that default limit to whatever you need.
New limit in Osclass 8.2.0 will be 4500 entries. Means if you do not want to always change this, make sure your regions has no more than 4000 cities.