I have two tables. The first only does calculations with spreadtab and has some final result that I tag (with spreadtab's ommand tab). Later, I want to reuse the value in another spreadtab, but I do not know how to do this. Here is what I tried:
\documentclass[a4paper,10pt]{article}
\usepackage[utf8]{inputenc}
\RequirePackage{booktabs}
\RequirePackage{spreadtab}
\RequirePackage{array}
\RequirePackage{tabularx}
\RequirePackage{tabu}
\RequirePackage{fp}
\begin{document}
\section{Try 1 - Using package FP}
\begin{spreadtab}{{tabu} to \textwidth {ll}}
@ A & 1234 tag(personalkostenI)
\end{spreadtab}
\FPset\personalkosten{\STtag{personalkostenI}}
\vspace{10mm}
\begin{spreadtab}{{tabularx}{\textwidth}{lX}}
@ B & \FPprint\personalkostenI
\end{spreadtab}
\section{Try 2 - using spreadtab}
\begin{spreadtab}[\STsavecell\personalkostenII{b1}]{{tabu} to \textwidth {ll}}
@ A & 1234
\end{spreadtab}
\vspace{10mm}
\begin{spreadtab}{{tabularx}{\textwidth}{lX}}
@ B & \personalkostenII
\end{spreadtab}
\section{Try 3 - Only using tag}
\begin{spreadtab}[\STsavecell\personalkostenII{b1}]{{tabu} to \textwidth {ll}}
@ A & 1234 tag(personalkostenIII)
\end{spreadtab}
\vspace{10mm}
\begin{spreadtab}{{tabularx}{\textwidth}{lX}}
@ B & \STtag{personalkostenIII}
\end{spreadtab}
\end{document}
For the third variant I get the error messages
