Arrows in Commutative Diagram in Tikz

Question

I tried to adapt the code for a diagram provided in an answer on this site: question. When I copy the code into Overleaf, it works and gives me .

When I adapted the code to the following

\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{amsthm}
\usepackage{tikz-cd}
\usepackage{pst-node}
\usepackage{tikz}
\usetikzlibrary{positioning}

\begin{document}

\begin{center}
\begin{tikzpicture}


\node (Q) at (0,0) {$M'$};
\node[right=of Q] (W) {$F_s$};
\node[right=of W] (E) {${(H_n)}_s$};
\node[right=of E] (R) {$T_n'$};
\node[right=of R] (T) {$\mathcal{N}_n'$   geometric};

\node[below=of Q] (A) {$\mathcal{M}$};
\node[below=of W] (S) {$F_{ss}$};
\node[below=of E] (D) {$(H_n)_{ss}$};
\node[below=of R] (F) {$T_n$};
\node[below=of T] (G) {$\mathcal{N}_n$   good};

\node[below=of S] (X) {$F$};
\node[below=of D] (C) {$H^N$};
\node[below=of F] (V) {$H^N_{ss}$};
\node[below=of G] (B) {$\mathcal{N}};


\draw[->] (W)--(E) node [midway,below]{$\tau$};

\end{tikzpicture}
\end{center}

\end{document}

it gives me

The nodes have worked, but the arrows don't; and if I leave out the arrows entirely it gives me nothing at all. Does anybody know what I'm doing wrong?

Thanks for any help.