Bug in populating PDF with XFA from VBA

I've been attempting to populate IRS tax forms with VBA.

--For text-type fields, I can just set Fields(<field name>).Value to the desired string, and the value is correctly stored.

--Checkboxes, however, although they appear to be populated when I view the form in the Acrobat window before closing it, come up blank when the form is next opened in Acrobat or Reader.

--By browsing the internal PDF structure in Preflight, I find that my populating code has correctly set the checkbox value (V), the AP, and the AS values for the checkbox in the Fields object of the AcroForm. However, it has not set the correct values for the checkboxes in the tags in the datasets code of the XFA object, whereas it has done so for the text fields.

--Call to Adobe's service line was of no avail; as soon as the operator heard the letters "XFA", she had all she needed to give me the brushoff: the form was created in LiveCycle Designer, it's not Acrobat's problem, I'll have to purchase Adobe Experience Manager. Which looks to be an enterprise-scale investment.

--I submit that the problem is still an Acrobat problem, because Acrobat, even Reader, knows enough to populate XFA correctly and to rely on it rather than the Fields to decide what to display. The AcroForm VBA plugin also correctly populates XFA for text fields, but fails to do so for checkboxes. Fixing the plugin for the next update will solve the problem completely. I need to get this information past the gatekeepers to the eyes of the Acrobat team.