After reading the message from Jessica, here is a link to a document I generated on how to align the cutter. After doing this mine went from just about cutting 3mm MDF at 7mm/s to slicing through it at 12mm/s to 16mm/s.
http://www.floatingwombat.me.uk/wordpress/?attachment_id=30
Excelent link, thank you Tim
Do the link still working?
Certainly Does!
This should take you direct:
http://www.floatingwombat.me.uk/wordpress/wp-content/uploads/2015/02/K40-Alignment-Instructions.pdf