[NTG-context] A question about layers

OK, after a pm from Mojca concerning my previous question I decided to look into the "layers" mechanism. It won't work for me - just nothing shows up. What am I doing wrong? Here's a minimal example: \starttext \definelayer[title][x=105mm,y=20mm] \setlayer[title]{This is the title.} \stoptext (I'd also like to be able to "anchor" the title so that (105mm,20mm) are the coordinates of the center, not the lower-left corner etc. How to do that?) TIA -- Marcin Borkowski http://mbork.pl