Hi Guys, sorry I did not realise anyone had replied. Thank you though.
I am using a single window, which is open to the GI light, and also two orange-coloured omni lights. I have deleted the omni lights before and the blotches were still there, so I am assuming that it must be something to do with the GI or possibly the rendering engine, however I have tried a host of different engines and nothing happened. I am not using an emissive material either so it cannot be anything to that.
@valerostudio: I will try the beta, but would you mind explaining 'blurred workarounds', sorry but my Vray terminology is fairly thin.
Cheers again,
Matt