align=center option of
\setupcaptions can align the caption in the middle of figure or table. It's OK with one-line caption text, while not so good for multiple lines of caption texts, for all lines align in the middle.
How to make the effect like the following example, which the first words of caption text from the second line on line up with the first word after caption label?
Figure 1 This is very long caption text as an example.