[NTG-context] Layer for all pages and for specific pages

Hi, I use a vertical line (realized as a layer) for a bilingual project. My question is: 1. How can I set this line on all pages? 2. How can I control, on which pages it is set, and on which not? I tried it with state=start/stop/repeat, but that did not work. Here my try: \definelayer[mybg] [x=0mm, y=0mm, width=\paperwidth, height=\paperheight] \setlayer[mybg] [hoffset=10cm, voffset=4cm] {\blackrule[width=1pt, height=\vsize, depth=0.5ex]} \setupbackgrounds[page][background=mybg] \setuptolerance[tolerant,stretch] \starttext \input knuth \page \input knuth \stoptext Thanks for help. Huseyin