Very simple. Of a piece of plastic, not really observing the quality of workmanship (it will still be closed anyway), we produce such a detail. The distance between the holes is just how much you need to shift the new picture (photo, interactive alphabet, etc.) relative to the old, existing holes. Insert the screw into another hole and fix it with a nut. M3 is enough "for the eyes", because you will not hang an elephant.
Fix the resulting "structure" on the wall and clamp it.
All. Hang up a calendar (or whatever). For extra strength, lay the washer and tighten with another nut. But this, especially if the design will be static, and you will not constantly “fumble” it, this is superfluous.
That's all wisdom. Successful implementation and use.