gform_advanced_settings Uncaught TypeError: Cannot set property 'gform_xx'

Hi im trying to extend gf and adding additional advanced settings utilizing the gform_advanced_settings hook, however when following the documentation (which referes to the example for gform_field_advanced_settings I get the error :
Uncaught TypeError: Cannot set property 'gform_xx' xx being the new setting option,,
how do I get advanced settings to save?

Hi David,
Thanks for the prompt reply, My work is in a Plugin (Im a plugin developer) and working on local machine,
we have decided to go another route, i.e the paypal add-on way,, essentially try this:

gform_field_advanced_settings example but replacing the gform_field_advanced_settings hook to a gform_advanced_settings hook (and changing the $position like the documentation says to refer to this example) there are other differences that make the gform_field_advanced_settings not work as an example for gform_advanced_settings I would suggest adding a specific example for the gform_advanced_settings documentation.