I'm sorry to hear. Doesn't matter who makes the car, if the dealer manages to stuff it up you aren't going to buy another :(
This may not matter now.. but the correct way of getting overspray off the exterior is to use a clay bar, not to buff the car. :(
To cover the interior is unforgiveable. :( Just keep documenting all this.
Be aware that landrover may offer to help you into a new car to get rid of the problem... but the disposal of the old one will probably be your problem :( And the dealers won't want your car (they know what is wrong with it) so will offer you no money for it :(
