It doesn't support either of those features (although a dictionary is being worked on).
I found the User Manual very useful for these sorts of questions: Lots of useful screenshots and explanations. (Click on the screenshots to view them at a readable size).
http://openinkpot.org/wiki/0.2/UsersGuide
The only thing I've noticed that isn't in the manual is a complete list of the actions you can assign to keys. (If you're going to use the number keys, I'd recommend customizing the actions. IIRC, the default settings include a "decrease font size" key, but not an "increase" one. Of course if you _don't_ use the number keys, then you just press the "zoom" button to get a list of font sizes).