Hi, raptorjr.
About debugging JS code. You should do this in browser, I recommend to use Google Chrome, as it's developer tools are great. If you use Windows just open HG in Chrome and then press F12. Developer tools window will appear. It has a number of tabs, like Elements, Console, Sources, Network and so on.
For debugging JS itself you use Sources tab. On the left side you can see the tree of files and open one you are interested in, or press Ctrl+O and start typing the filename. When the file is open you can add breakpoints like in VS by clicking on the line number.
In the Network tab you can monitor all requests from client to the server and corresponding responses.
I recommend you to google how to use Chrome Developer Tools, it is very powerful instrument for developing web applications of any kind.
Also notice, that HG's UI is built using jQuery Mobile framework.