Transparency issue with particle effect (fog)

I need some fog for a unity project I am working on but I want it to be low lying fog so I am using a particle emitter, I thought I would save some time by searching the asset store for a base to work from. I am using LemonSpawn's lazy fog. It all started fine but then a friend tested it on her PC only to find that the transparency was displaying as black, this issue has migrated onto my PC and all I know about whats causing it is its something else within the scene, as the fog in its own scene works fine...

But then In my game scene... it displays like this^ (sorry for bad pic it kept exceeding upload size limit)

I really do hope someone can help as its been driving us mad, thanks in advance