Composite Transparency?

Hello all.

I’m having a little trouble compositing my scene.
I have created a plasma ball (The electric current within a glass orb) and I am trying to apply a blur and gamma to the electricity. When rendered on its own the electricity looks how I want it to however because it is surrounded by a transparent sphere I am unable to render the effect properly. I have tried all sorts of different render layers etc. but unfortunately the image renders the electricity as its normal render AND its composite.

If any of you can help I would be very grateful.

Here is an image of my scene, the surrounding orb being in wire frame


This thread goes nowhere unless you provide a .blend file.

Without a blend very hard to tell you what to do… But, you probably will need to render in layers if you are not doing this already.