Note:
If you are importing an XML schema that contains an <xs:include> or <xs:import> schema element, the element’s schemaLocation attribute must be set to a file reference on the local file system.
The name must be one word and no longer than 127 characters. The first character of the name must be a letter or an underscore (_). The remaining characters may be letters, digits, hyphens (-), underscores, or periods (.).
In the Use XML Data Root Element Name menu, select the root data element that will be used to name the root subform of the form design. This menu is populated with the global element declarations in the XML schema.
(Optional) Select Transform Incoming Data and click Browse Livecycle browse button To create a data connection to an XML schema and XML data file to search for and select the XSLT file that will be used to transform incoming data for the form design.
(Optional) Select Transform Outgoing Data and click Browse Livecycle browse button To create a data connection to an XML schema and XML data file to search for and select the XSLT file that will be used to transform outgoing data for the form design.
Note:
The at symbol (@) before name in the Data View palette indicates that this node is an attribute of an option node, and #data indicates the actual value of the option node.
See also 

To create a data connection to an XML schema and XML data file