Need help with modifying an experiment

[HamidLD]

Hi everyone, I've been learning Java and jspsych recently to run an experiment online. So far, the experiment looks like this:

where the participant has to press the left or right arrows to select an image and get a feedback. Now, I want to make the experiment look like this:

which has two more images (two rows), and in each trial either the upper or lower paired images will be chosen automatically (forced choice, shown with * sign ) and the participant has to choose one of the other paired images (shown with a rectangular bar).

Here's the code so far 2-arm bandit.zip, which I have to modify. Now I was wondering I should modify the plugin and add display lines for the two new images, but I'm not sure how I can force-choice the upper or lower rows. I'd appreciate it if you point me in the right direction.