I have just had a deeper look at it in version 25.
And the display order has no effect on the 'Composite Structure' at all that makes any sense to me.
I thought is was the numbers in the prefix that was throwing it off, but even without numbers at the beginning of the names, the order just seems to be random.
Might be a good idea to report this to your local Archicad support.
One of the forum moderators.
Versions 6.5 to 25
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