Hi Janet
I have the same van, not the GT60 though, and I had the same problems when I collected mine in January. I tow with a Skoda Octavia, max noseweight 75kgs. I have during the year mastered the noseweight to a fine degree. Some of things, others will say is a no-no but here goes: Front locker has 2 4.5kgs gas bottles, one full, one half plus spare wheel. Lounge lower storage has kids sleeping bags and pillows plus small electric hoover we carry. Lounge overhead lockers have light clothes. Wardrobe has clothes and towels. Kitchen cupboards as you'd expect. Toilet compartment has waste water and fresh water carriers. Fixed bed underneath has shoes/boots, 4 lightweight outdoor chairs, roll up alu table, bats/balls for the kids plus various light caravanalia bits. When we travel I place my wheelclamp, hitchlock, toolkit and both electric leads secured over the axle.
Also, are you checking the van when it's at the correct altitude as hitched to your car, plus don't trust the gauges you can buy, mine was 15kgs out. Use the bathroom scales with suitable plank of wood.
Hope this helps and enjoy the new van.
Ian