I have never seen wingmen with the AN124 at MAN either, however it does usually have a follow me which is normal practice for strangers.
And we did pay host to the Demo A340-600 some time ago, dont recall it causing any problems.
I believe the airport have potential long term plans for widening taxiways, which would entail demolishing the fire station, and closing stands 60 - 66.
In relation to diversion alternates for the A380, I think CDG with its acres to spare would be a good choice for any LHR bound aircraft, as seems to be the case with many airlines already.
Just out of interest does anybody have the wing span and lenghts of the mentioned aircraft.
A380
A340 -600
B747
A124