I think there is a space problem after formulas inside itemize environments.
\starttext
\startitemize
\item Eeny, meeny, miny, moe
\placeformula
\startformula
\text{Numbered formula: the space after is correct.}
\stopformula
\item Eeny, meeny, miny, moe
\placeformula[-]
\startformula
\text{Unumbered formula: the space after is too big.}
\stopformula
\item Eeny, meeny, miny, moe
\stopitemize
\stoptext