[atreis]

Water leaks are the most common complaint for new Gulfstream trailers it seems. (Mine had loose fittings.) Check all of the fittings, including drains. Fortunately, once the plumbing is all tightened up, that's often the only major issue.

Low water pressure: I'd bet there's a flow limiter in the showerhead (usually a little plastic washer-like thing that restricts the size of the opening). Most people would likely want that in order to keep from draining their freshwater tank and filling their gray too quickly. Anyway, take off the showerhead and you should be able to find and remove the limiter. (If you camp at places that don't have full hookups, you might be better off just getting used to the lower flow though.)

GFCI tripping ... Perhaps it's a bad GFCI? (It's not really common, but does happen.) If it only happens on that one GFCI, I'd replace it. If it happens in multiple places, but only with that fan, then I'd replace the fan.