BMW X5 Bio Diesel fuel injection system fault, please HELP?

Hi

I have a BMW X5 e53 3.0D on from the year 2003.

I have just encountered a problem today. I will tell what has happened, and hopefully someone can HELP?

I used biodiesel for the first time yesterday by a mix of about 50/50 regular diesel to bio diesel, (I know I probably should have used more diesel now). A day later the car went into limp mode on a bank and slowly got to the top, the problem then went and the car drove as normal.

A day later than that I drove the car for about 10 miles and on the same bank (coincidence?) The car went back into limp mode and eventually lost all power and came to a stop, with a note on the onboard computer saying 'fuel inject problem'.

The car now starts sometimes or doesn't even start. I have used some diesel injector cleaner (Redex) to no success.

I am waiting for a new fuel filter to arrive which will be changed.

Has anyone ever had the same problem?
Does anyone know a possible fix for this?

I greatly appreciate all help from everyone, big or small so thanks in advance.

Sean