Is it possible to access the media library or nexgen gallery from a gravity form or similar form?

I would like to create a form that will allow different users to create post on my site without using the standard wordpress layout. The admin panel will be fully customized and look completely different than the basic wordpress admin area. I want users with certain permissions to be able to navigate between the front and back-end with ease.

I have created a page in the front end and I am using gravity forms post fields to allow users to create new post, but I would like users to be able to select photo's from the media library, or better yet, nexgen gallery, and not their local directories.

Is this possible with gravity forms or any other plugin? Or am I better off customizing the add new post area in the back-end instead?

Thanks in advance for any enlightenment on this query.