hi,
don't know if this will help as I don't quite understand the problem, but some times the wiring is three phase and earth, and sometimes three phase and neutral, which is blue or black in a normal single phase supply,but the old colour code for three phase was red,yellow blue.
three phase does not need a neutral to work, as the phases interact with each other to push the motor.
but you must earth the new machine, which you will probably do with the armouring.so the blue wire in the ceramic connector MAY be for a neutral
I don't understand why the connector with the blue in is causing a problem, just connect the three phase lines in the correct order to the isolator. if it is the colours that are causing a problem in the new cable, check the new colour coding that we have had to adopt.
if your new machine runs backwards, reverse any two wires that are next to each other on the new feed.
hope this helps in some way.
if in doubt ,call a sparky.