I'm not sure what the limitations are on the trial version.
You need to know which version of SQL Server you're connecting to - Windows Server 2003 is the operating system, NOT the database. On the workstation where you are running Crystal, you must have the MS SQL Server clients software installed.
When using the Report Wizard, select "New Connection". It may take a few seconds for the list to open up. Scroll down to OLE DB (ADO) and search that list for MS SQL Server. You can also set up an ODBC connection and connect to that.
-Dell