There is no issue with Shuriken and tk2d, but in a lot of cases, you will need to rescale the particle effects to fit the 2D scene.
The author of that package says the same thing on his product page:
Please note that due to the way Shuriken is done, scaling the effects is not easy (not impossible, just tedious). The cubes in the demo are 1*1*1m, so the effects are "realistic" in size. There is a great effect scaler (link) that might help a lot though.
You can try that effect scaler link to help scale the particles, or you can do it manually - its a pain but doable.
Also, I don't know how that effect caster script works - you should ask the author for support on that specifically.