Well peoples... she's up and running, and playable again, the new flipper buttons arrived today from RTBB, so i wasted no time in fitting them when i got home from work!! but first i had to overcome a few switch issues before i could have a proper game. I had several rollover switches that were intermittent and no amount of cleaning would make them work reliably   In the end i added .047uF caps across all the rollover switches, which seemed to eliminate the 95% of the problems i was having.. there's still one of the top rollover switches that plays up very occasionally, but after adding the caps and playing about a dozen games, its all working pretty sweet now  

Also i DID reseat the connector on the MPU for the pf switch matrix, which cured another problem i had with the drop targets, so i still have to re-pin the switch matrix connectors, and possibly replace the pin headers on the MPU, which will be done soon.