Movement sounds are tied to the fixed movement type data and not platform specific. Same with weapons. There are only set types. If there is more than on sound, like blast1, blast2, etc., the game will choose from the group at random.
Quick question on the above -- for the original sounds that have numbers (blast1, blast2, blast3). Can I add more sounds by simply incrementing the number on the end (blast4, blast5... blast23, blast24, etc...) or am I limited to the same quantity as the originals as well?
Likewise, if there is a sound that doesn't have a number (slingshot.wav), if I want to add more, can I simply start appending numbers (slingshot1.wav, slingshot2.wav, etc...) and have it switch to randomly selecting one?