Login page "Sign In" button not working

I have read through the readme file for SwiftyDropBox and followed all of the directions. The app compiles without error. When I run in the simulator and click the button I have setup to connect to the appropriate code to launch the auth workflow the page loads but no images are included. there are question marks in place of the images. The "Sign in" button is visible and I can enter my email and password for DropBox but clicking on the sign in button does not do anything. I have made sure that I am passing the topmost view controller ... 

            var topController = UIApplication.shared.keyWindow?.rootViewController
            while let presentedViewController = topController!.presentedViewController {
                    topController = presentedViewController
                }

DropboxClientsManager.authorizeFromController(UIApplication.shared,
                                                          controller: topController,
                                                          openURL: { (url: URL) -> Void in
                                                            UIApplication.shared.openURL(url)
            })

I have included the necessary code in my app delegate with the proper app key. When I hit "done" on the page I get the 

"Authorization flow was manually canceled by user!" message in my console properly. 

No idea what is going on here?! 

XCode version 10.1

IOS SDK 12.1

iOS Simulator:  12.1: (16B91)

SwiftyDropBox v 5.0