We have found on some vehicles that the ignition coils have a "dirty" low rpm signal. This "dirty" signal can cause the erratic low rpm display like your video shows. While the installation instructions do not mention it, we have found that triggering the window switch with the fuel injector, instead of the ignition coil, tends to give a "cleaner" signal and has often times eliminated the rpm display flashing issue your video shows.

Hope this helps!