The following example solves now your problem on my machine without the ugly solution with \indentation.
\unprotect
\def\OTRONEdosomepagefloat#1[#2]% {%\checkwaitingfloats{#1}% \global\setbox#1\vbox {\unvbox#1% \vbox to \textheight {\doifnotinset\v!high{#2}\vfill \box\floatbox \doifnotinset\v!low{#2}\vfill}% \goodbreak}% \doinsertfloatinfo \dochecknextindentation\??bk \dorechecknextindentation}
\protect
\setupindenting[medium,yes] \setupfloat[figure][default={page,high,none}] \setupfloats[indentnext=yes]
\starttext
\dorecurse{2}{\input knuth \par}
\placefigure [] [fig:bild] {Text} {\hrule width 6cm height 14cm depth 0cm\relax}
\dorecurse{3}{\input knuth \par}
\stoptext
Hope it works for you too.
Wolfgang
Yes, it works! But aren't there any unwanted sideeffects? There must be a good reason for Hans, to NOT include this in the output-routine. Btw. are the ??xx (here ??bk) Variables document somewhere? Wolfgang