2. The rear of the floats are dragging on the ground when using the new trolley with the sand wheels, hardly any clearance under the sterns, are the floats low or are the tyres underinflated? It being only the second time I've used the trolley. Its a lot of hard work dragging it all up the beach, harder than I think it needs to be?
Both AI and TI ama will drag at the rear. You can use a roof rack strap at the stern looped over the hull and under both ama and back through the buckle. Tighten it up and the ama will clear the ground better. Don't over inflate the sand tyres as it will make them less effective and void their warranty.
Regarding problem #1 that occurs when the drive is not inserted correctly. Make sure the drive is seated correctly on the front drivewell ledge.