All of the Candy products (Particle-, Text and Widget Candy) come as a lua source, which means you just need to copy them to the computers you will be using them on. No license checking is done.
Personal note:
I have all of the products above, and they haven’t been updated for a very very long time, which makes me wonder if support has more or less been dropped. I’ve also had great difficulties contacting the developer when I had issues.
If you’re on a Mac, there’s a great alternative here:
https://71squared.com/particledesigner