Internal Error when viewing portfolio items

This plugin is exactly what I’m looking for.

I installed it no problem, and added my first 5-6 portfolio items no problem. Suddenly, every time I click on ‘portfolio items, I get a 500 internal server error.

I tried uninstalling it and re-installing it, with no success. I can still add items, and access the rest of the plugin, but I cannot view it, and when I add the shortcode [nimble-portfolio hide_filters=”true”] to any page, it returns a 500 internal server error.

I can still access some of the posts I created:

http://chadperlmutter.com/wordpress_7/portfolio/portfolio/

but when I access the portfolio page with the shortcode, I get the error:

http://chadperlmutter.com/wordpress_7/examples-work/

I did upload and add about 12 pictures to one post- that is when the error occurred.

Please advise- I want to get this working so I can use it ASAP.

https://wordpress.org/plugins/nimble-portfolio/