[NTG-context] error with footnotes blackrule

Hi, todays minimal gives an error: Runaway argument? \letvalue {\??vn \c!rule :c:\currentnote }\normalnoterule , \v!normal \ETC. ! File ended while scanning use of \p!compareprocessactionD. <inserted text> \par <*> ./notetext.tex ? The cause is "\blank[2mm]" in this example: \def\MyRule{\blackrule[width=18mm,height=0.4pt]\blank[2mm]} \setupfootnotes [rule=\MyRule] This harmless vertical space did it up to now. What's the phrase that should be chosen instead? Steffen