I noticed that the head of the screws is very small to distribute the tension to the acrylic panels. If u tightend the screw to strong you can break the acrylic glas. The brass inserts you inserted are also not perfect aligned so the washer can spread the force a bit.
You can print these washers in PLA, PETG or TPU . I used TPU.
The washers are a bit bigger as the screw head. The height is 0.6mm.
Here you get the ARC mod https://www.printables.com/model/356301-arc-for-bambu-lab-p1p
The author marked this model as their own original creation.