Building effective Power BI reports for your app

You may already know that Power BI allows developers to easily create powerful custom visualizations for your application's unique needs. In this video, we explain the core concepts of building Power BI custom visuals and show you how to get started with your own custom visuals now.
IT seems like this instruction is outdated, first the command typings install dt~d3 --save does not work until you install d3 version 3.5.5. Secondly, you still get errors to provide 4 argumnet to
private svg : d3.Selection<SVGElement>.
Can you kindly provide updates on that?
Source Code Available here:
https://github.com/microsoft/PowerBI-visuals-sampleBarChart
Please advise, having down loaded Power BI where can I go to see all the visualizations that Abbsource or any other source provides.
I want to see some really cool dash board speedo-type GUIs, choose one and the start to up load data to it.
regs
Alan