A simple test - Take a container that measures one litre graded in milli litres. Add to it exactly 1 litre of water and weigh it accurately. It should weigh exactly one kilogram. That means that it has a SG (a specific gravity) of 1.

Take exactly 1 litre (1000 milli litres) of fossil diesel and weigh it. It should weigh about 820 grams - SG of .82. Take exactly 1000 milli litres of your biodiesel and weigh it. hopefully, it should weigh around 840 - 850 grams.

That means that it is only slightly thicker than fossil and should be OK in common rail fuel managed systems.
As I said before my Disco has done 90,000 kms on biodiesel (total 115,000 kms), is easy to start hot or cold and runs really smooth.

My friend who is a diesel fuel system/injector maintainer says that those who do not refine their biodiesel properly and run it in common rail engines "can" have trouble down the track.