I try to show a decimal comma, instead of point in the following question:

\element{group}{
\FPeval\VQfor{trunc(16+random*10,0)}
\FPeval\VQsol{round(1000/VQfor,0)}
\FPeval\VQnonA{round(100/VQfor,2)}
\begin{question}{questionName}\\
Here come the question \VQfor{} mm?
\begin{choiceshoriz}
\correctchoice{E= 1:\VQsol}
\wrongchoice{E= 1:\VQnonA}
\wrongchoice{E= \VQsol:1}
\wrongchoice{E= \VQnonA:1}
\end{choiceshoriz}
\end{question}}

I try to use \def\AMCdecimalPoint{,} in the preamble (as from doc, 5.6.1.2, page 40), but it does not work, it still shows a point.