Hi Dancy and welcome to the forum - if fact - you're the first one ever to ask a question here!
I can't tell you any ways to make a demo filter a full version but if you want to create a cartony look without paying for extra filters check out THIS TUTORIAL.
I would also recommend using the filters available in MOTION.
Make sure you are accessing all available Motion Filters in FCP as per this pic:
Look at the filter VECTORIZE COLOR in particular.
Hope this helps - by the way - how did you stumble across the site?
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Doug Suiter.
Freelance Director, Promos, Post & Creative.
LondonFCP/SydneyFCP Administrator.
Find Local FCP Operators (Sydney & London) at the FCP Talent Registry: www.FCPTalent.com