I cannot see how a wastegate impacts starting.
I wonder if the valvetronic is supposed to 'park' itself at a specific location at shutdown, perhaps?
I dont have a gasser, so dunno. It is pretty common for people to damage the VTmotor when replacing the valvecover.
My 19 year old M5 (235k) is pretty much perfect....

an indulgence I guess, but if something breaks it gets fixed.