101010 Artemesia

Hi everyone, I don't want to open a new thread with identical topic, so I ask here. My question is not about the old box, which was really cool and easy to handle. The Folder in the viewer is called 'Merchant outbox'. It is a folder in my inventory and (like the linked arcticle says) I can also open it from the top menu. (not Me/merchant outbox, but World/merchant outbox in singularity) But I can't drag and drop anything into the window and I can't 'copy to Merchant Outbox'. In both cases the same error appears. 'The Marketplace store is returning errors' My product is not listed in my marketplace store. There is just no way to get it there. So, this must be viewer-related. (Singularity 1.8.6) Or do I have to activate the store somehow? I'm thankful for any help. Thanks & Greets!