Selecting one of several MCs and move independently of others

Thanks to help from members on another thread (here) I have a script that enables me to face and move a single MC using arrow keys, which will continue to move in the same direction at a constant rate after a key is pressed.

What I’m looking to do now is exactly the same thing but with multiple MCs on screen (say 2+), but be able to ‘select’ each one independently of the others with the Mouse and use the same direction keys (or buttons) to control them in the same manner without affecting the direction or movement of the other(s).

Example: 2 objects. Mouse click on one object and use an arrow key or button to send it off in a given direction. Then, mouse click on another object and send it off in an independent direction, using the same keys/buttons without affecting the first object’s current motion.

Can anyone give me an idea of what I would need to do to accomplish this? I’ve found plenty of tutorials which talk about creating MC buttons, but not sure how to proceed from there.

Thanks in advance for any help.