Kickstarting my Matlab experiment with clicking objects

Hey all,

I am working on a project for short term memory, where responses are recorded by clicking an object on the screen. There are two slides that will be shown, and one will be slightly different from the other, kind of like a spot the difference kind of a deal. There will be 4 objects on the screen, and I need some help getting that all together.

Right now, I have been able to put up a gray screen, but cannot put my objects in there. I also want the objects between each slide to change stimuli, like one of the 4 objects rotated between the two slides, or one of the objects changed color from the last slide to this one. I want these stimuli changes to be completely random, but I have no idea how to do any of that.

What are some articles or pieces of advice you can give me? I am looking for

-Putting clickable objects on the experiment screen

-Two slides in one experiment

-Looping the two slides, them being identical but only one object stimuli changing between the two slides

-Having those slides repeat for 5 times, 5 pairs of slides, each time with a new object stimuli.

-Putting a couple seconds between those slides

-Changing the object stimuli randomly, maybe with an equation of some sort.