been reading this thread, and really sounds like you need to get the car to someone who knows what they are doing ,
first of all ,,if the engine starts with easy start its most likley a fuel issue? ie
1, lack of fuel or pressure ,,check , pumps , filter, injectors, fuel pressure sensor
2, dirty injectors will cause poor starting and poor running , always difficult to diagnose a problem without actually there
i wouldnt change all 4 injectors, they are too expensive at £190 each , i recently changed a faulty one and the engine is now running great
good luck