I made two minor changes in the script so that 1. checkboxes are being saved with a boolean value of true or false when convert equals true and 2. unselected radios come with a defaultValue that can be provided via second parameter.
This way I can directly work with the data and don't have to deal with undefined values.
No rocket science, but very handy for my uses.
In case You like to have it, I have placed it here: Download in full code and minified. Changes are commented with // DDTech