Well, a good night's sleep helps. Back at it.
Took each (8) refill cart out, removed the reseter , checked the pins etc and replaced. One had a tiny piece of plastic from the cutting from the oem cart, blew it away etc. Having taken and checked every refill cart I also took the oem one cart out and put back. Installed all the carts, reset the machine and turned on. Same result, no carts recognised.:mad: Gave each cart a gentle nudge (no hammer yet) and tried again. Miracle, only two carts not showing. Another gentle nudge and try again. SUCCESS. All 9 carts showing.
Moral? Be patient and ensure everything is in good contact. A bit of good luck also helps.