Hi Matthew,
I agree with all the comments made about having the equipment and the know how, however we all have to learn somewhere... There was a time when the world's expert on these looked at one for the first time.
From memory these use approximately 90V on the injectors. The ECM will not fire the injectors until a minimum rail pressure is achieved, about 160 bar on this car if I remember correctly. Check for excessive injector leakage, remove the injector leak-offs, close off the return pipe with a pipe clamp or you will get diesel everywhere. Get an assistant to crank the engine and observe the amount of leakage from each injector, in most cases if one is faulty the difference is so marked you cannot mistake it. Obviously it is preferable to use a set of leak-off bottles but if you take precautions to catch the leakage with tissue and don't crank for too long and get diesel everywhere then you should be ok. If your assistant is on the ball you can do this test with no spilt diesel at all.
Not being able to read rail pressure on cranking is a big draw back for you, is the battery fully charged? I find many ECMs stop talking on cranking if the voltage drops just a little bit too far.
Shaun