The new engine is in every release, but it's disabled by default - instructions on how to use it are in the sticky - basically you need to do the conversion from the command line with two specific arguments:
--new-pdf-engine
--debug-pipeline "/some/directory"
For all the cli arguments and examples refer to the manual:
http://manual.calibre-ebook.com/cli/...#ebook-convert
http://manual.calibre-ebook.com/conv...ormatting-demo
The above won't generate an actual ebook for you, it will just dump an html version of the pdf into the debug folder. You can convert the html to an ebook by re-importing it to Calibre and converting from zip to whatever.
You'll still wish the layout was better after you see the output, but for two column it will probably give you manually salvageable results, which the production version won't do. By layout I mean many paragraphs will probably need to be manually fixed - the sentences will be correct, but it's not good at detecting appropriate paragraph breaks/page breaks as I recall.