--------------------
Here's the error text:

SqlException
 Implicit conversion from data type text to nvarchar is not allowed. Use the CONVERT function to run this query.

Source     : .Net SqlClient Data Provider

Stack Trace:
   at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection)
   at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj)
   at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj)
   at System.Data.SqlClient.SqlDataReader.ConsumeMetaData()
   at System.Data.SqlClient.SqlDataReader.get_MetaData()
   at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString)
   at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async)
   at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result)
   at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method)
   at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method)
   at System.Data.SqlClient.SqlCommand.ExecuteDbDataReader(CommandBehavior behavior)
   at System.Data.Common.DbCommand.System.Data.IDbCommand.ExecuteReader(CommandBehavior behavior)
   at System.Data.Common.DbDataAdapter.FillInternal(DataSet dataset, DataTable[] datatables, Int32 startRecord, Int32 maxRecords, String srcTable, IDbCommand command, CommandBehavior behavior)
   at System.Data.Common.DbDataAdapter.Fill(DataTable[] dataTables, Int32 startRecord, Int32 maxRecords, IDbCommand command, CommandBehavior behavior)
   at System.Data.Common.DbDataAdapter.Fill(DataTable dataTable)
   at MicroFour.StrataFrame.Data.DbDataSourceItem.GetDataTable(DbCommand Command, OnChangeEventHandler CallBack)
   at MicroFour.StrataFrame.Data.SqlDataSourceItem.GetDataTable(DbCommand Command, OnChangeEventHandler CallBack)
   at MicroFour.StrataFrame.Data.DataLayer.GetDataTable(DbCommand Command, Boolean RegisterNotification)
   at MicroFour.StrataFrame.Business.BusinessLayer.FillDataTable(DbCommand CommandToExecute)
   at MicroFour.StrataFrame.AddIns.DTEprojectsBO.FillProjects(String[] ProjectPaths)
   at MicroFour.StrataFrame.AddIns.PartialClassBuilderDialog.BuildProjectNode(PartialClassBuilderVSProject Prj)
   at MicroFour.StrataFrame.AddIns.PartialClassBuilderDialog.BuildTreeView()
   at MicroFour.StrataFrame.AddIns.PartialClassBuilderDialog.InitForm()

It's SQL Server 2000 (SP3).  I believe that it has all patches/etc. at least up to a month or
so ago.

Do you have any special characters in the paths to your project files?  Probably not, if you're just trying to open the tutorial, but it seems that when passing the project paths to SQL Server to retrieve the project records, it's trying to convert it from an AnsiString (ASCII) to unicode... not sure why.  What happens if you create a new project using the StrataFrame Windows Application template (either C# or VB, doesn't matter) and try to open the BOMapper?