\usemodule[visual]

\newdimen\Bleed
\newdimen\maxWidth
\newdimen\maxHeight
\newdimen\doubleWidth
\newdimen\topOffset
\newdimen\bottomOffset

\Bleed=3mm

\setuppapersize[A6][A6,oversized]
\setuplayout[%
	location=middle,
	marking=on,
	grid=yes,
	%backspace=12.5mm, width=80mm,
	%topspace=12.5mm, %height=125mm, % Text+Footer
	%header=0mm,footer=10mm,
  cropoffset=0mm,
  bleedoffset=\Bleed,
  trimoffset=-5mm,
]

\setupbleeding[offset=\Bleed]
\maxWidth=\dimexpr\paperwidth + \Bleed\relax
\maxHeight=\dimexpr\paperheight + 2\Bleed\relax
%\doubleWidth=\dimexpr2\maxWidth\relax
%\topOffset=\dimexpr\topspace + \headerheight + \Bleed\relax
%\bottomOffset=\dimexpr\bottomheight + \footerheight + \Bleed\relax

\definelayer[picbg][x=0mm,y=-\Bleed,width=\maxWidth,height=\maxHeight] %
\setupbackgrounds[page][background=picbg,state=start]

\definemakeup[fullpage][
  page=no,
  doublesided=no,
  headerstate=empty,
  footerstate=empty,
  pagestate=start,
]

\startmode[arrange]
\setuppapersize[A6][A4,landscape]
\setuparranging[2UP]
\stopmode


\starttext
\fakewords{50}{100}

% full page image, left page
\startfullpagemakeup
	\setlayer[picbg][
    x=-\Bleed,
    y=-\Bleed]{%
    \fakeimage{\maxWidth}{\maxHeight}{\maxWidth}{\maxHeight}
		%\externalfigure[dum][height=\maxHeight,width=\maxWidth]%
    %\fakeimage{5cm}{3cm}{10cm}{5cm}
	}
	% set caption into footer on top if picture
	\setlayer[picbg][
    x=\backspace,
    y=\dimexpr\makeupheight + \footerheight\relax,
  ]{%
    \inframed[
      frame=off,width=fit,autowidth=force,
      background=color,backgroundcolor=white]{%
      \vbox{\fakewords{2}{20}}
    }%
  }%
\stopfullpagemakeup

\fakewords{200}{250}

\stoptext
