Checkboxes don't work

I have a Word document that I convert to PDF, and then to a form. It’s a five-page long legal-sized checklist with hundreds of checkboxes
and radio buttons.

I learned a long time ago that I can replace bullets with a square symbol (Webdings: 112) and have them automatically convert to checkboxes
when I create the form. I also insert this symbol in places where I need a checkbox for an item that is not on the bulleted list.

I know that this checkbox conversion doesn’t work unless the font is AT LEAST 10 pts, so that’s always the first thing I check. But whenever I revise this beast of a form, this only works about ½ the time. Half of the checkboxes create during form conversion, and the rest I have to insert manually, rename and align. Consequently, this form takes me most of a day or longer to edit with any revisions.

The font throughout the document is Calibri 11 pts. I’ve tried converting it to a form in both Acrobat X and Acrobat XI, with pretty much the same results. I also tried doing it a page at a time, and that didn’t change the results either. Neither did copy/pasting it to a new document. I do NOT have time to retype the whole thing from scratch in a new document, if I can help it, so that's one test I haven't done.

The bullets are all the same because I apply a Word “style” to the lists, so they format automatically. I use the same blank template to create all my forms, with
the same Word styles and settings. Most of the time this works, but in random instances it does not. I can’t figure out what the code is behind the scenes
that is messing up.

Can someone please help?

Thanks!