Question: In MS Word.

If heading one is numbered using roman numbers, when the figure caption also includes chapter numbers, roman numbers will be used like this: "II-1", but what I want is "2-1". How can I achieve this?

![enter image description here](https://i.stack.imgur.com/pO4C2.png)

Answer: 
I've got a better solution: 

Number the chapter headers with Arabic numerals and then use hidden formatting (ctrl+shift+h) to hide the number and manually write "Chapter I", "Chapter II", etc. It's not the prettiest solution, but I think it's the easiest. ToC should use whatever you've written there so you can manually change that too if you need to.
You only need to make a new level numbering and new heading. For example, if your numbering thant link to heading is until heading 3, you could add level 4 for new heading that you make for figure. For example you make a new heading and name it as Figure. Then link the level 4 numbering to Figure heading. The issues come: how to make a table of figures for this heading. It is easy, in the options menu while you insert table of figures, change the styles column to be Figure. And voila you made it.