Attempting to replicate the gradetable macro of the exam package in Latex

main.tex

% In response to the stackexchange question: https://tex.stackexchange.com/questions/680066/customising-gradetable-to-group-multiple-choice-into-1-column-with-the-exam-cl
% You can compile and view the pdf version of this Latex document at: https://crixet.com/?gist=d433f7deda0eb630dad9b98bb3b281b9

\documentclass[addpoints]{exam}
\usepackage{tabularx}
\usepackage{xcolor}
\usepackage{multicol}
\begin{document}


Original from \textbackslash gradetable

\vspace{1em}

% Uncomment to double check the second table matches the first.
\gradetable[h]

\vspace{1em}

Manual recreation of \textbackslash gradetable

\vspace{1em}

% Manually create a duplicate of the table above, with MC columns consolidated.
\renewcommand{\arraystretch}{1.6} % Adjusts the row height
\setlength{\tabcolsep}{12pt} % Adjusts the column width
\begin{tabular}{|@{\hskip 5pt}l|*{5}{c|}} % first column is left-aligned with a 5pt horizontal padding, and the next 8 columns are centered.
\hline
Question: & MC & \multicolumn{1}{c|}{5} & \multicolumn{1}{c|}{6} & \multicolumn{1}{c|}{7} & Total \\ % Merged cells for questions 1 to 4, and individual cells for questions 5 to 8, now using numbers only for questions 5 to 8
\hline
Points: & 4 & 12 & 12 & 12 & 40 \\
\hline
Score: & & & & & \\
\hline
\end{tabular}

\begin{questions}
\question[1]
\question[1]
\question[1]
\question[1]
\question[12]
\question[12]
\question[12]
\end{questions}

% The issue was that the number of columns in the header did not match the number of columns in the rows below. Added an extra column to each row to fix the alignment.


\end{document}