Not yet. The Marketplace is still young and we have not yet built the infrastructure required to buy and sell items for money. For the time being, every item is shared free of cost.
As part of the upload process, you can set the Creative Commons license appropriate for your work and everyone who uses your item agrees to abide by that license when they download it. For more information about Creative Commons and the licenses they define, click here.
Yes. Active items can be edited to a limited extent without requiring re-submission, but changes to an item's assets or content file will require re-submission for review.
If you experience an error that impacts your upload of files, there are several possible causes:
Assets are specifically not cached while an item's status is 'Draft' or 'In Review', but once an item is approved, assets related to that item are cached.