when copying into a collection with only 1 sub-resource, specific sequence selection not working

On FF3 for XP on Curent.dev, I copied a resource (first testing with another member's, then one of my own), and selected a target location for it where it was a collection with only one sub-resource, as in:

Collection
--Existing sub-resource in Position 1

The target location I selected (to test that it would not appear at the bottom in the sequence) was as follows:

Collection
--Newly copied resource A
--Existing sub-resource previously in Position 1, now w/ new copy A, would be in Position 2

Upon successful completion of the process, I went to view the newly copied resource A, but the collection appeared with this sequence:

Collection
--Existing sub-resource previously in Position 1
--Newly copied resource A

To work correctly, it should have appeared with A in Position 1 and existing sub-resource in Position 2.

Note that (not sure if relevant, but will mention), my copies were all marked Private.

(I did not see this problem when a collection contained more than 1 resource; in all those tests, the final sequence was correct as chosen.)