2 column sidebar with Antenna House

I am having an issue with creating a 2-column sidebar using DocBook 1.76.1 and Antenna House 5.3

Having been a user of RenderX for quite some time, I am finding (thankfully) that there is a lot of overlap with extensions with AH.  

That said, it appears that AH is more flexible in letting you create a multi-column layout in the middle of the current flow.

As per the documentation on the AH site (http://www.antennahouse.com/xslfo/axf5-extension.htm#axf.column-count)

I created the following:

<fo:block-container axf:column-count="2" axf:column-gap="1pc">

</fo:block-container>

There are fo:block elements inside the container.

When the content is rendered, it does have 2 columns, but content is always in column #1, nothing ever flows to the second column.

I tried setting the axf:column-fill="balance" (which, according to the doc, is the default anyway) and that didn't help.

I also tried to give the block-container an explicit height (which is not ideal and if that were a requirement, would make this not usable for me) and that didn't help anyway.

I also tried using a float (through the side bar processing instruction) and not using a float, neither worked.

There seem to be NO examples out there that I could find of anyone actually using this.  

Anyone have any ideas of what I could be doing wrong?

Thank you in advance.