Membership plugin - photo upload page

Hi,
I'm just playing around with the membership plugin to see what I can do with it. I made a quick 'Photos' page to see if I could allow users to upload photos.

I used this and it worked fantastic -
http://www.interactivetools.com/iforum/Products_C2/CMS_Builder%3A_Plugins_%26_Add-ons_F40/Allow_Logged_in_Users_to_Access_Upload_Form_P85546/gforum.cgi?post=81668

I'm wondering though, is there anyway to list on my photos page which user uploaded the photos? I noticed a system field called updatedByUserNum so I added the line

Uploaded by: <?php echo $record['updatedByUserNum'] ?><br/>

But it just brings up the number of that user. I can't seem to get it to bring up the "username" field and can't figure out how to make that part of the photos section without making a field someone has to fill out manually (don't want this).

Any help appreciated :)