Has any progress been made in the past few years implementing modifiable separators for captions under MKIV? This was raised as an issue by (at least) Mojca Miklavec in December 2010 (http://www.mail-archive.com/ntg-context%40ntg.nl/msg51542.html) and by Andy Thomas 18 months later (http://www.mail-archive.com/ntg-context%40ntg.nl/msg63937.html). (Their issues with stopper have been resolved. In MKIV it is numberstopper.)

Here is an MWE demonstrating the problem. It compiles cleanly, but the separator remains the default period. With MKII, it generates a figure with a hyphen and not a period.
\setupcaptions[separator=-]
\setupexternalfigures[location=default]
\starttext
\chapter{Chaptername}
\section{Sectionname}
\placefigure[here][fig:1]{Caption}{\externalfigure[cow.pdf]}
\in{See Figure}{.}[fig:1]
\stoptext

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Rik Kabel