Ah.....resolvers and SMB is the 'storage' medium for the data.....that would make sense then (I should really do some more background reading about this).
Cheers for pointing that out, it answers a whole host of questions I had lined up......
The system is back operating again and after a fine calibration, the tolerance of the application allows for a slight deviation of alignment for which the client is not too concerned about as during their setup procedures, they check the master locations and tickle them on a regular basis as when they replace some of the external components between jobs, introduce some deviations for which they re-teach out......not ideal, but that's their procedures.
Many thanks for all your comments, very much appreciated indeed, consider the thread closed.