So this is free? It depends upon what you are looking for.
The player engine of Tiny Things (which includes 10 particle effects) is freeware. If there will be a collection of free *.pfx files it would be a very efficient freeware tool which could be attached to the Gamestudio engine. It is also granted to use TinyThings in your own projects. If they are non-commercial your are free anyway, if thery are commercial the only limitation that the credits include the phrase additional effect programming: superfluxus /TinyThings - and 2) that you get a registered user.
The program that you can download here is a fully functional program, just the SAVE-function is blocked. That means you can do anything - but you may not store your own effects.