[NTG-context] repeat layer recto pages

I want a particular layer to repeat on recto pages only, but I don't want this to happen in frontmatter, only in bodymatter. This is what I have done, just before the first chapter after \startbodymatter (but unsuccessfully; the layer repeats for every page at the moment. I must have omitted something). \startbodymatter \setupbackgrounds  [rightpage]  [background=butterfly] \startchapter[title={Chapter title}] \definelayer[butterfly]     [x=0mm, y=0mm,repeat=yes,width=\paperwidth, height=\paperheight] \setlayer[butterfly]     [hoffset=.99\textwidth, voffset=1cm]     {\externalfigure[bfly.jpg][width=1.5cm]} \setupbackgrounds[page][background=butterfly] etc. Any thoughts? Julian