Thank you @AxLed ! I forgott to mention a power & a reboot button attached to the GPIO Pins and exactly that (false positive reboot-script execution) was the root of the Problem. I solved it with rechecking the pins for LOW-state after a 1/10 of a second. This issue bugged me for several months. Thank you again!

hello, I installed the module but stay loading on the MM. Any advice ? Thanks marc