Help Wiring New Converter to Motorhome

So I got everything hooked up...everything seems ok for an hour or two. I left the fridge running on 12v just now and will check in the morning hopefully no fuses blown or anything. When I add additional batteries can I just install another fuse and hook them up to the second 12v output on the pd9260? I'm assuming the two positive outputs are bridged? Also how can I switch this to a gel charger? I was told I could with re arranging a jumper internally. I noticed that the voltage has shown that the starting battery does not charge, is that normal? Oh and one last question, how fast does the alternator typically charge the house battery?