Slider: Add Slider popup blank

[WillStrohl]

The extension loaded fine, I placed it on home page and says I need to add slider. I click pencil and add slider and a popup opens. It is blank, attached is a screen shot. I'm using DNN 7

if I click settings I get: A critical error has occurred. Object reference not set to an instance of an object.

I'm sure Im doing something wrong but I can't seem to figure it out.

Please advise.

ORIGINAL: https://dnncontentslider.codeplex.com/workitem/13140