Hi Hans,
In the following test, \in{}[] typesets the correct part/chapter/section number, but doubled up as in "Chapter 2.32.3" instead of "Chapter 2.3".
\starttext
\placecontent
\part[pt:foo_bar_baz]{Foo, Bar, Baz}
\chapter[ch:foo]{Foo}
\in{Chapter}[ch:baz1]
\chapter[ch:bar]{Bar}
\in{Section}[ch:foo]
\chapter[ch:baz]{Baz}
\in{Part}[pt:foo_bar_baz1]
\part[pt:foo_bar_baz1]{Foo, Bar, Baz 1}
\chapter[ch:foo1]{Foo 1}
\chapter[ch:bar1]{Bar 1}
\chapter[ch:baz1]{Baz 1}
\stoptext
I don't urgently need a fix or anything. I just wanted to get this on the queue.
Kevin