If you hover over "Cancel" and "Tech", it'll open up a tooltip that shows the meanings.
EDIT: Scroll down to "Damage Scaling" on http://www.dustloop.com/guides/bbcs2/systemGuide/systemGuide.html for information on proration.
If you need further explanation on cancels, techs, or proration after reading that frame data and the guide, be sure to hit up the beginner mode subforum.