What Developent Environment are you using for developing Custom Widgets? Especially to be able to develop the Settings part as well.
Currently I'am trying to figure out how good it works with Visual Studio 2012 to have the benefit of debugging.
If i only have to develop one Widget the best way for me was to create an application and add some Basic Widets and download it. Then i've created a WebProject with Visual Studio based on the application. Within the Application i've created a new Widget and added the Widget to the config.json. This worked pretty well for developing and debuging the Widget itself, but it got more complicated when trying to work on the Settings-Part. Therefor i created a new "dummy-widget" for development and copied it to the settings folder of the original widget (+ renaming Widget.* => Settings.*).