Good advice Jade:)
I figured out this was basically the problem:
template::form::set_values does not set values in the FORM from the array reference passed to it. This is because the upvar is not referencing the correct level. Also, once this is fixed and values are being set from the array to the FORM, if a value exists in the array that is not in the FORM, an undocumented/unexpected error is thrown.
And submitted a bug report.
