TabularX environment with some fixed width

Question

I'm creating a table for a procedure. I selected 3 columns to be able to put subpoints intended. Unfortunately, with multicolumn it doesn't go to \textwidth anymore, but rather selects the X and keeps that constant (at least I'm assuming this is why the table isn't \textwidth the full columns through). My questions are:

(1) how to widen the column (see Note row), so Note fills the table to the right

(2) how to have [a] etc. only intended to 1cm (as Note does).

Thank you for your help.

\documentclass[a4paper,12pt]{book}

\usepackage{ltablex}
\setlength{\parindent}{0pt} % never indent first line

\begin{document}

\textbf{Procedure:} The following basic procedure MUST be followed to amend a Motion.\\
\begin{tabularx}{\textwidth}{m{1cm} m{0.5cm} X}
\multicolumn{2}{l}{\textbf{1.   Mover of Amendment:} }&
\textit{"Mr Chairman/Madam Chair, I} (state name) \textit{move an amendment that,}\\
&[a] & \textit{the words \textellipsis be omitted"}  OR\\
&[b] & \textit{the words \textellipsis  be substituted for the words \textellipsis "}    OR\\
&[c] &\textit{ the motion be altered to read \textellipsis"}  (If the alteration is a major one)\\
& \multicolumn{2}{X}{\textbf{NOTE:} The mover of an amendment may put his/her proposal at any time in the debate after the original motion has been seconded.}\\
\multicolumn{2}{l}{\textbf{2.  Chairman:} }&    \textit{"Have we a seconder for the amendment”?}\\
& \multicolumn{2}{X}{If there is no seconder, the amendment lapses and the discussion reverts to the original motion.  If there is a seconder, continue as follows.}\\
\multicolumn{2}{l}{\textbf{6.  Finally:} }& \\
&(1) &  If the amendment is LOST, the debate is resumed on the ORIGINAL MOTION.\\
&(2) &  If the amendment is CARRIED, the amended original motion is now open for further discussion.\newline The mover of the ORIGINAL motion still has a right of reply.\\
\end{tabularx}

\end{document}

Edited after question/answer from Zarko:

This is a sample how I would like it to look. In Zarko's answer, it doesn't take the words in different column and comment underneath indented.

Answer 1

I guess that you like to have something like this:

For this result are used: enumitem and ragged2e packages, and, sice ltablex diple reformat tabulary table, you need to add command \keepXColumns for preserving features of X column(s):

\documentclass[a4paper,12pt]{book}
\usepackage{ragged2e}       % <--- aded
\usepackage{ltablex}
\keepXColumns               % <--- aded
\usepackage{enumitem}       % new
\setlist[enumerate]{nosep=0pt,
                    leftmargin=*,
                    after=\end{minipage},                  
                    before=\begin{minipage}[t]{\linewidth}\RaggedRight 
                    }
\setlength{\parindent}{0pt} % never indent first line

\begin{document}

\textbf{Procedure:} The following basic procedure MUST be followed to amend a Motion.

\begin{tabularx}{\textwidth}{m{1em} X }
\multicolumn{2}{l}{\textbf{1.  Mover of Amendment:}}
                            \\
    &   \textit{"Mr Chairman/Madam Chair, I} (state name) \textit{move an amendment that,}        \\
    &   \begin{enumerate}[label={[\alph*]}]
    \item   \textit{the words \textellipsis be omitted"}  OR
    \item   \textit{the words \textellipsis  be substituted for the words \textellipsis "}    OR
    \item   \textit{the motion be altered to read \textellipsis"}  (If the alteration is a major one)
        \end{enumerate}     \\
    & \textbf{NOTE:} The mover of an amendment may put his/her proposal at any time in the debate after the original motion has been seconded.
                            \\
\multicolumn{2}{l}{\textbf{2.  Chairman:}}
                            \\
    &   \textit{"Have we a seconder for the amendment”?}\\
    &   If there is no seconder, the amendment lapses and the discussion reverts to the original motion.  If there is a seconder, continue as follows.                \\
\multicolumn{2}{l}{\textbf{6.  Finally:}}
                            \\
    &   \begin{enumerate}[label=(\arabic*)]
    \item   If the amendment is LOST, the debate is resumed on the ORIGINAL MOTION.
    \item   If the amendment is CARRIED, the amended original motion is now open for further discussion.\newline The mover of the ORIGINAL motion still has a right of reply.
        \end{enumerate}     \\
\end{tabularx}

\end{document}

However, I'm not sure, how the result should be and if for it you really need table environment. Probably enumerate nested in description environment will give similar result.