Marshmallowhead

I found one thread that dated back to 2013, so I'm asking again. I was told magic boxes were obsolete by one person but then another person told me the only way I can sell breedables is through the magic box. However, they aren't syncing to my marketplace store. Is creating new items through the magic box not an option now? Maybe I uploaded them wrong? I did box them and name the boxes so there aren't repeats. How can I sell my breedables without renting a store inworld?