When using right float with grid, paragraphs do not wrap correctly arround 
the figure. Consider the following example and compare the output with and 
without \setuplayout[grid=on]

\setuplayout[grid=on]
\starttext
\startplacefigure[location={right,none}]
   \externalfigure[cow][width=0.3\textwidth]
\stopplacefigure
\input knuth

\stoptext

Aditya