This may be old news to everyone else, but it caused me enough frustration I thought I'd mention it here 
The samples that come with StrataTrain ( the third party training video series ) not only use SF 1.4 and must be fiddled with before they can run ( by the newbies who are least qualified to do so 
) but somewhere along the way field names were changed by SF in the sample database so any control bound to cust_lname or cust_fname property will cause an error.
For notes on the fiddling see the thread here "Update Training Videos" ( persevere to the end ) There is a mention there of the field name change, but the solution of running the BO mapper only changes the properties created in the partial class. The form controls must be manually set to the correct field names.
I know how frustrating it is for everyone when you are in overwhelmed newbie mode and samples don't work, so I thought I share this.
I think there may be another vestige of this change, BTW, in the FillbyLastName() method in the VB Winform Tutorial
Public Sub FillByLastName(ByVal LastName As String)
'-- Establish locals
Dim loCommand As New SqlCommand()
'-- Build the query
loCommand.CommandText = "SELECT * FROM Customers WHERE cust_lname = @cust_lname"
'-- Add the parameter
loCommand.Parameters.Add("@cust_lname", SqlDbType.NVarChar)
loCommand.Parameters("@cust_lname").Value = LastName
'-- Execute the command to fill the business object
Me.FillDataTable(loCommand)
End Sub
note the cust_lname = @cust_lname