Its not a choke although it has a lever in the same way a choke has, its still just a fast idle control.
Okay, well it shouldn't cut out like its doing, it should just run normally like you wouldn't know it was cold. Like your 748 used to i guess so there is certainly something wrong somewhere.
Rushjob has some kind of magic electric box thingy plugged into his ST4S (same motor as your bike) which does a similar job to a PC3 but is a bit cheaper i think.
I suspect something like that is the only way your bike is going to run correctly.
Might be worth letting the dealer have another crack at it though.
Of course i could be talking rubbish, hopefully someone more knowlegable than me will be along soon!