You got good answers to your questions, the only thing that I would do for #5 is to take a reading with the MH plugged into shore power across your pos and neg terminals of your battery, it should read 13 plus volts, if so your converter/charger is working. Unplug the MH from shore power and let the battery sit over night and take a reading the next day, it should read about 12.6 volts if the batteries are fully charged and connections are good. If you post those reading here I am sure your issue will be solved. If your batteries are only a year old it should be something simple. What type of batteries do you have? Is there enough water in each of the cells? Are the connections clean and tight? Is your battery disconnect switch in the on or use position?