Hi Alison
To create Licenses you need to have the service activated and defined the license types you need. Means you have to Activate Legal Regulation EAR for imports and exports.
To classify products, means to assign ECCN numbers you have to have the Numbering schemes for export lists and import lists and you have to assign them to the Legal Regulations.Without doing this you cannot assign ECCN numbers to products.
Also you need to have contents (ECCN Numbers) uploaded in the system or you have to create ECCN numbers manually.
Note that if you have created ECCn numbers manually for a Legal Regulation system will not allow you to upload the contents by xml files.
Hope it is clear now. If you have any more doubts feel free to get back to me.
Keshav Murthy