I can agree with you that the UI of the Azure Storage Explorer might be have been changed and the screenshots from the KB article and the instructions we have provided may not apply to the current view. We are aware that this can happen and we have noted this in the KB article.
What I can suggest is that you refer to the Azure Storage Explorer documentation in order to get more details about the latest updates in the UI and how to work with it: http://storageexplorer.com/
In addition to this, the errors that are thrown in the controller of an MVC widget should be logged in the error log files and you should be able to review them when you download the logs from Azure.
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