Help Needed with Custom Drop-Down Field

[ppdigital]

I've successfully installed PhotoPost 5.2 and vBulletin 3.5.4 on my new domain: http://www.photosharingforum.com

I'm creating a photo sharing site for photographers. I'd like to include a custom drop-down field that would allow members to assign a Creative Commons license to each photo.

Creative Commons offers 6 licence variations:

Attribution Non-commercial No Derivatives
Attribution Non-commercial Share Alike
Attribution Non-commercial
Attribution No Derivatives
Attribution Share Alike
Attribution

Content visible to verified customers only.

I was able to create a custom drop-down list in the category admin panel. I uploaded a test image, selected a license, and was able to save the image ok, but I have not been able to determine how to do the following:

1 - Make this field required for all uploads. If you don't select a license from the drop-down I'd like an "Please Select a License Type" message to be displayed to prompt user.

2 - Currently the license is only displayed under the medium sized image:

Content visible to verified customers only.

Can the value from my new custom drop-down field (the license type) be shown under the image thumbnails also?

3 - Can I make the displayed license name a hyperlink point back to the associated Creative Commons license?

Example:
Attribution Non-commercial

4 - And finally, would it be possible to search/sort on license type?

I really like the concept of Creative Commons. I think it would encourage more users to upload photos knowing they could control how their work would be licensed.

Flickr and OpenPhoto are currently offering this type of licensing. Seems to work well.

I would be very appreciative if some other PhotoPost users could point me in the right direction on what files I'd need to modify

Thanks a lot!

[DefenceTalk.com]

Here is a thread on required fields when uploading pictures:

Title and Description Mandatory in Photopost pro?

[ppdigital]

Thanks for the info!