Let's say I have 1 face down card which is Blast with Chains trap card. which when activated is an equip card to a monster and it gains 500 atk points. My opponent activates a Mystical Space Typhoon to destroy my Blast with Chains card. Am I allowed to activate the Blast with Chains trap card and equip my monster or does speed spell come into effect here, taking into consideration that Mystical Space Typhoon is a quick play spell and Blast with Chains is a normal trap card?