Some teething problems but alls well that ends well - here's some tips
1) Minor problem: the knob on the right - the temp control - was not attached and kept coming off in the hand while showering. It took a bit of detective work to discover that the silver bobble on the end could be popped off via a small indent and that there was a screw rattling about inside that could be used to affix the knob to the end of the cartridge mechanism. This also meant that the position of the knob had to be carefully calibrated to ensure the temperature markings were aligned with the actual temperature.