\myblank
\input knuth
\stoptext
</context>
We have the same problem with a flowchart:
<context source=yes>
\runMPgraphicsfalse
\usemodule[chart]
\setupindenting[yes,medium,next]
\startFLOWchart[test]
\startFLOWcell
\location {1,1}
\name {start}
\shape {loop}
\text {Start}
\stopFLOWcell
\stopFLOWchart
\starttext
\input knuth
\FLOWchart[test]
\input knuth
\stoptext
</context>
This can be solved in the following way:
<context source=yes>
\runMPgraphicsfalse
\usemodule[chart]
\setupindenting[yes,medium,next]
\definefloat[flowchart][default=force,indentnext=no]
\setupcaption[flowchart][number=none]
\startFLOWchart[test]
\startFLOWcell
\location {1,1}
\name {start}
\shape {loop}
\text {Start}
\stopFLOWcell
\stopFLOWchart
\starttext
\input knuth
\placeflowchart{}{\FLOWchart[test]}
\input knuth