In a recent situation we were asked to install a remote SalesLogix 7.0 SQL2000 database on a notebook with SQL 2005 Server. We were able to remove SQL Server 2005 in this case but when we attempted to install MSDE we were prompted to use a strong password and the installation stopped until we added that switch. We knew we wanted a named instance configured to use Mixed Mode. Here is the syntax.
From a command prompt execute d:\MSDE2000\setup INSTANCENAME="SALESLOGIX" SECURITYMODE=SQL SAPWD="SLXMaster"