A question about sky flash missile

Hi guys. A while back there was disussion on some forum about AIM-7 Sparrows. It was said that the AIM-7 is launced directly from the rail, that is it does not sperate from the aircraft before turing its own motors on. Well, I am asking about Sky Flash since it seems to be based on the Sparrow. However the Tornado ADVs carry them under their fuselage slightly recessed. The question is how different is Sky Flash from Sparrow, and can the AIM-7 be modified to be fired from different pylons. Thanks in advance.