Do yourself a favour and try to get some actual weights. Hookup and take it to a scale. Using the brochure and dry weights can be highly inaccurate.
A trailer with a dry weight of 4200lbs is likely several hundred pounds heavier once options, propane, batteries etc are added. I suspect your loaded weight to be well over 5k even lightly packed.
Same goes for your tongue weight. You say 460lbs (which is still too light for your stated 4900lbs weight). As you load the trailer your tongue weight will increase. The listed 460lbs is for an empty trailer and doesn't include the propane tanks and battery which are usually mounted on the tongue and will easily add 100+lbs to the tongue weight.
