I have in now (well for the last 6 weeks) with the exact same fault codes, the exact same fluid in the exhaust and smoke from exhaust.

I've removed all the exhaust system from turbo and the DPF looks clean as does the CAT.

The turbo does look quite carboned up but i don't think its the cause.

I had the injectors tested and all passed, that ruled them out so now i've got new glow plugs to fit and then hopefully i'll re-assemble and give it another go.

Around £40 worth of rubber gaskets just for the inlet manifold.

Afterwards I may give it a dose of the cleaning fluid SP sell as it can't do any harm.

Sorry its not much help but at least you know its unlikely to be the injectors. I thought they maybe causing an overfuelling issue.

thanks
lee