datablock PlayerData(PlayerTopDownArmor : PlayerStandardArmor)
On this line you are defining a datablock called PlayerTopDownArmor and making it based off the existing datablock called PlayerStandardArmor. Since the datablock PlayerTopDownArmor already exists, it is simply overwriting that datablock. Simply change the datablock name and it should work. However, you might want to also change the datablock to copy from for no reason other than to make the file smaller. If you do this, you only need to include lines that are changing, in your case; everything to do with jumping. If you have trouble, i'm more than sure somebody here will spoon-feed you.