I am making a platform shooter game and the gun of the character is seperate sprite. (I don't feel like making all animations for all different guns) So the problem is that when I use always -> set position at *coordinates* "main character", the weapon sprite seems to be kind of slower than the character. It's not really that big deal but it's annoying.
Fastloop doesn't really need to be used for this unless the character is using one of Clickteam's built in movements, although it can make things a little easier.
Your best bet is to have the player controlling an invisible object, and then to make both the character and the gun's positions set to the same co-ordinates as it. This way if the gun can't catch up with the player, neither can the character, so nobody will notice anyway.