Can possible help with number 3 as i had problems last week,i was told that if a BMW is parked close by and uses their remote to open the car they have been known to mess up Landrover alarm systems.
We started a similar load of b0110cks when I worked at Nissan in the early days of OBD...Basically anything that wasnt understood by the tech guys was always put down to OBD picking up stray signals from nearby vehicles....
Got to the stage where nobody wanted to park in town center multi storey but would prefer to risk car being stolen down a side street....Thing to be noted is that very few vehicles had any sort of RF device that could have affcted them even if parked next door on same frequency the alarm/immobiliser plips are coded so near impossible to find another vehicle that it would work on.
Try walking round any large group of motors pressing your fob...betcha it wont open any......then go back to the place with BMW bu11sh1t and ask them to do the same
