Types, Views and Gravity Forms

I actually have a couple of problems. I have set everything up and everything appears the way it should be except:

1. The custom field for Job Description does not appear for WP Types in Gravity Forms
2. Fields keep disappearing from my custom fields list and
3. I get: ERROR 500 – INTERNAL SERVER ERROR when I attempt to view the page that has the shortcode [wpv-view name="Job Listings"]

The page is http://cmsaaz.com/cmsaaz-new/job-opportunities/

I'm happy to provide login credentials – just let me know?

Thanks!