John, I'm sorry you're still experiencing this problem which I had several months ago, and actually tried helping you with it but couldn't replicate it anymore.
In a PM you sent me you specifically mentioned '94 Upper Deck Minors and I see that you have #54, #148, and #225 in your collection AND they're the ones showing on the Want List, too.
A few minutes ago I tried adding just to that set as I have two from it, but it just added what was missing. I was thinking maybe the glitch is within the set itself, but it seems to function for me.
I'll give it another try and will be recording the moves in case it does it again. Not promising results from my efforts, but I do know the exact issue personally.
Follow my blog - I Identify as a Card Collector.
“Aslan didn't tell Pole what would happen. He only told her what to do. That fellow will be the death of us once he's up, I shouldn't wonder. But that doesn't let us off following the signs.” - Puddleglum in The Silver Chair by C. S. Lewis