Captions with Chapter Numbers from a Custom Style

I'm using Windows 10 and Office 2016.

I have a specific custom (let's call it 'MyHeading1') style in a template which I use to create a numbered heading (like 1.0, and so on).

I now want to create a caption for a figure I insert after that heading style, e.g. Figure 1-1 if it follows heading 1.0. Or Figure 2-1 if it follows heading 2.0.

This is possible, of course, if I use the Word built-in Heading styles. However, for operational uses of the template in different countries/languages it is not possible to do. It must be based on a home-made heading style.

Jay Freedman MVP has written a great article explaining how to create captions with chapter numbers but the underlying message is "You cannot create them from YOUR styles; only from the Microsoft built-in Heading styles"

He has also included an Add-in to allow captions to work from personal styles. This, of course, is copyrighted and I cannot give it to all and sundry.

Does anyone know of a site/forum where such a solution has been discussed and where the VBA is visible for public use, please?

Thanks for any pointers.

Roderick