Hi Mark,

Various things can result in it looking as if Guide's
planetary positions are all way off. The two big ones are
time and location settings.

For time: make sure you've got the correct time zone
selected, and are using the Gregorian calendar.

For location: go into Settings... Location, and make
sure that your 'home planet' is Earth and that your altitude
isn't something like several AU. (If you were looking for
something demanding more precision, you'd also want to check
your latitude/longitude. But for the sort of thing you're
looking at here, position on the earth isn't so important.
Jupiter's moons look pretty much the same from any part of
the earth.)

-- Bill