Posted November 7th, 2016
I've attached an experiment that functions how you've described. Just replace the text in the events with your desired images. Check out the notes in the editors for specific details.
In this experiment, the 15 events will present indefinitely until the participant presses the space bar. When the space bar is pressed, the remaining events in the trial are skipped. Although the presentations are set to loop, the experiment still ends.
How? Because the presentations will only loop if a block takes 15 seconds to end (via macros). Each event takes 1000ms, so a block will only end before 15 seconds if events are skipped. And events are only skipped if the space bar is pressed.
Lastly, the reason there are two blocks with the same structure and behavior is so the block timers function appropriately.