Felicia hall / crankshaft position sensor

Good afternoon everyone.  Apologies if this question is in the wrong place or for any other snafu, I'm relatively inexperienced at this.

I have a 1998 felicia glxi estate, 1.3 mpi engine. I have a suspect hall / crankshaft position sensor which shows previous physical damage, the sensor is scratched and dented, which I'm guessing perhaps occurred during a clutch breakdown before I purchased the vehicle.  

The symptom is that the car will occasionally die for no apparent reason during driving.  The remedy appears to be to disconnect the battery for 15 minutes, restart, and the car drives perfectly.  

Skoda portugal advise that the correct replacement part is no longer available, but has the part number 047907319A.  I purchased an aftermarket item off ebay claiming to be the equivalent.  The car will start with the new sensor, but idle is a little rough and the car hesitates or dies when attempting to pull away. 

I have disconnected the battery to try and clear any error codes and allow the computer to adapt to the new sensor, but this has not helped.  My question is, is it likely that the replacement sensor is bad, or is some magic required with full vag-com setup to allow the computer to work with the new sensor?

Thank you in advance for any pearls of wisdom on the subject.

Best regards, Richard