Presenting predefined subset of stimuli to participants

OS: Windows 10
PsychoPy version: v2021.1.4

Hi all,
I’m still quite new to Psychopy so apologies if I miss any important details or anything, just let me know what to clarify. For my experiment, I am looking at adaptation aftereffects to body size. My stimuli CG images - there are 18 distinct identities (i.e. different skin tone, limb length) and each identity has 25 images. These 25 images make the identity go from small to big in body size. There are four conditions relating to body size (i.e. big torso, neutral legs; small torso, neutral legs), but these only apply to the adaptation stage.

My practice, baseline and test phase use seperate body halves (i.e. torso and legs) to form a full body and these are manipulated independently. My adaptation phase has precreated bodies, thus one image rather than two seperate halves.

What are you trying to achieve?:
The practice phase has 2 identities attached to it. The baseline, adaptation and test currently have the remaining 16, however I only need 8 to be presented. Furthermore, I would like the baseline and adaptation phase to present the same 8 identities (i.e. 3-11) and the test phase to present the remaining 8 (i.e. 12-18). Ideally, this would also be counterbalanced, so some participants receive the aforementioned presentation and others receive the reverse (i.e. baseline and adaptation = identities 12-18; test = 3-11).

What have I done already?
For the above problem, I haven’t done much to address it as I’m not sure how! However, my experiment currently has all phases inputted as well as four conditions for the adaptation phase. I’ve set up the conditions using “$‘conditions’+expInfo[‘group’]+’.xlsx’” and this is working fine, but I’m not sure how to add onto what I’ve already got. I’ve uploaded an image of my flow if this helps.

Thank you very much and please let me know if I can provide any further details.