Linux command-line steps to make a single-page version:
pdftoppm -png Maleghast_666_Update1.pdf Maleghast
convert Maleghast*.png -crop 2x1@ 'out-%02d.png'
rm out-00.png out-01.png
cp Maleghast-01.png out-01.png
img2pdf out-*.png -o Maleghast_666_single.pdf