On Tue, May 19, 2009 at 5:17 PM, Willi Egger <w.egger@boede.nl> wrote:

> Don't worry, Holland is still fine...
>
>
> But the problem I refer to is not in the dimension whether or not it is
> spelled correcltly.
> The error is still the same:
>
> ! Undefined control sequence.
> <argument> \reporttextprefixerror
>
> \secondoftwoarguments #1#2->#2
>
> \rightlabeltext ...ts \let \reporttextprefixerror
>                                                  \doreporttextprefixerror
> \...
> \labeltexts ...eftlabeltext {#1}#2\rightlabeltext
>                                                  {#1}
> \doifundefinedelse #1->\ifcsname #1
>                                   \endcsname \@EA \secondoftwoarguments
> \el...
> <argument> ... {\??ef \??ef XY\currentheadnumber }
>                                                   {\useexternalfigure
> [\s!d...
> ...
> l.14 ...er][width=\the\dimexpr.5\textwidth\relax]}
>
>
> \starttext
> \chapter{One}
> \placefigure
>        [here]
>        []
>        {A figure}
>
>  {\externalfigure[XY\currentheadnumber][width=\the\dimexpr.5\textwidth\relax]}
> \stoptext
>
> Willi


With...

\starttext
\chapter{One}
\placefigure
[here]
[]
{A figure}
% {\externalfigure[XY\currentheadnumber][width=0.5/textwidth]}
{\externalfigure[XY\currentheadnumber][width=0.5\textwidth]}
% {\externalfigure[XY\currentheadnumber][width=\the\dimexpr.5\texwidth\relax]}
\stoptext

I get: see attachment.
-- 
Alan