Hans Hagen
can you play with:
\unprotect
\unexpanded\def\startregisterseewords {\par % \ifhmode\crlf\fi \begingroup \setfalse\c_strc_registers_page_done \dostarttagged\t!registerpage\empty \useregisterstyleandcolor\c!pagestyle\c!pagecolor}
\unexpanded\def\stopregisterseewords {\dostoptagged \endgroup}
\protect
That fixed the original test file. But the problem resurfaced upon adding one more level of nesting (the "more nesting..." line). Here's the revised minimal example. \unprotect \unexpanded\def\startregisterseewords {\par % \ifhmode\crlf\fi \begingroup \setfalse\c_strc_registers_page_done \dostarttagged\t!registerpage\empty \useregisterstyleandcolor\c!pagestyle\c!pagecolor} \unexpanded\def\stopregisterseewords {\dostoptagged \endgroup} \protect \setupregister[index][n=1] \starttext hello \index{area}area and \index{area+ellipse}area of an ellipse more nesting \index{area+ellipse+today}area of an ellipse today \seeindex{area+United Kingdom}{United Kingdom, area} \blank[3*big] \placeindex[criterium=all] \stoptext -Sanjoy