User are shown a cached wishlist of the others in the group - if someone only has a few items on their wishlist, then everyone in the group will see a similar spattering of items.

If everyone in the group purchases those items, and puts them in the pool, then you are likely to get an item back that is the "same" (but it is not the same as the one you put in, it is the same item, but it's impossible for the system to give you back the same item ID, it will just go to melody).

If one person has an item on their wishlist, and 3 users buy that item and put it in, it's very likely the user with it on their wishlist got the item, and two other users. This isn't "not being distributed to the right people", it's that there was more than one in the pool. It will then try to divide things equally after going through wishlists as a consideration.

This is a massively complex system that tries to take into account many, many factors. It learns over the month how much sP you are willing to spend and will attempt to group you with similar users. It tries to take wishlists, value of items put in, etc, into account when distributing items. It is never going to be perfect.

That group had 8 Shinwa's Orb in the pool. Someone (you, and others) must have had it on their wishlist, and everyone in the group donated one (or more).

There just isn't a great way to do item dispersal when that happens -- it tries to give one to the people who have it on their wishlist.... and then it needs to hand out the rest. It looks like from that screenshot that you got items from your wishlist? If the pool has duplicate items, they've got to go somewhere.

This just isn't going to be a perfect system. It's got to take a bunch of inputs, and no one in the group is going to be happy every night. It's up to you if you want to participate or not, but I'm not planning on making significant tweaks to the algorithm. I am planning to run a survey sometime next week from people who've done at least 3+ to validate the feelings in this thread. If this is happening to less than 5% of the groups daily, that is basically what I expect with a system trying to do what this is.

There have been some changes made to Mysterious Melody, and are there still any remaining issues at this point?

Changelog entry for the changes made: https://kumos.subeta.net/changelog/14