I am not certain if it could work here, but I have a couple of AVL DiTest emissions testers and have made a little app to capture the RPM output based on grabbing the textbox the rpm is displayed in, in the ditest software. It means you can use their fantastic vibration analayser to get the rpm out just by connecting it to the block somewhere.
yes
A new version of the sensor is available now in the shop. It has a sensitivity adjustment that allows to manually adjust it to reject the noise and keep the signal we want. Together with the "Next edge rejection time" option, it's sufficient to get a reliable signal.