(player)You must make them do 0 velocity after they didnt press the button to move.
(npc) make them do 0 velocity (bunch of different method) this is my method (and maybe others)
Make the npc do this when they werent supposed to move
You can make the #Coin created a block that is non-collidable and make it save between levels..... (block should be invisible too!) , the block should sent a message to the block it is supposed to send to, that way the block accepts the message.