All records correctly show the selected FEU in the dropdown when editing an
individual record.

However when the FEU field is included in the item admin list (FEUDropdown
RenderForAdminListing($id, $returnid) method), only the first FEU username is
displayed for every record in the list.

Workaround was to:

1. create a new itemtab.tpl in module_custom/ListIt2MyModule/templates
2. in the template include {$uid=cms_utils::get_module('FrontEndUsers')}
3. In the custom fielddefs loop put:

                {if $fielddef->type == 'FEUDropdown'}
<td>{if
is_object($feu)}{$uid=$fielddef->value}{$feu->GetUserPropertyFull('firstname',$uid)}
{$feu->GetUserPropertyFull('lastname',$uid)}{/if}</td>
                
                {else}
<td>{$fielddef->RenderForAdminListing($actionid,
$returnid)}</td>
                {/if}

NB: above gives firstname and lastname FEU custom properties, not username.