I used a 2d particle effects program called Timeline FX which has some great effects. It can output PNG sequences at any resolition with their alpha maps. I then used Carrara to texture a plane with the animated sequence with alpha maps. This plane can be used in any 3d scene. I used a high resolution output of 2k so the effects can be used in HD work.
I also subdivided the plane on some effects and inseted a simple bone structure so I could animate the effects shape in Carrara.
If you download the sample and go in to the texture editor you’ll see how it is made up.
Using animated textures is a lot faster than using Carraras particles as some shots don’t need the full 3D particle effect.
Hope this helps
The nice thing about Carrara is that if you have a png, Photoshop file, etc. with a transparency, you can use it directly without having to set up a separate alpha channel in the shader.