Test and Main do not share databases, so you'll need to create an
account on Test and (re)upload your data to Test as well.
However, here's a trick for moving datasets between Galaxy servers:
use the 'save' link next to a dataset (the link for the 'disk' icon)
as the URL for a dataset that you want to 'upload.' This will enable
you to quickly move datasets between Galaxy servers without having to
upload again from your computer.
Also, we're working on functionality that will make it easier to move
Galaxy histories between servers, but it's not quite ready yet.