A couple of hints, some valid for every DC-DC:

1) never connect or disconnect the +12 cable without having it disconnected from the battery, Faston connection can be poor and you'll get an huge spike connecting it manually
2) disconnect it from the battery when changing the timer jumpers
3) NEVER wire your amp remote wires to the two pins on the M1, just use the positive one, if you need to groung it (some amps need it) place a fan or a resistor in serie to avoid short circuit. If you do not do it, short circuit WILL appen and WILL damage your M1 for sure (on mine the shutdown logig stopped to work after a bad amp wiring)
4) remember it's a COMBINED 90w, using a calculator never gives you the assurance it will work for you, take care of the 12v load (2A max)