Sorry to hear you've still got problems. There is an American site devoted to the d24 (email to
d24-owner@lists.subtend.net if you want to join) in the archives of which is a discussion of ways to prime a pump. The no-nonsense way apparently is to rig up a can on the roof and let gravity do it. Does sound rather messy and would definitely prove to be were I to give it a go.
There is a "spare" engine which in the garage, with a pump on it so if you happen to live close to wembley you are welcome to try it!
My only other suggestion besides that of bringing either car or pump to your local friendly diesel specialist is to mail Peter Milnes, the register keeper, who is particularly knowledgeable about the d24, as he owns one and is a mechanic
My money is still on the trouble being a pump seal based on craig8661's experience.
john