The slowness was caused by the Custom Field Properties I had in the main BO, following your suggestions I did the following to overcome this issue:

1. Make my main BO CFP overridable.
2. In the report's BO I override the CFP using the logic suggested by Greg to create a temp BO with all the lookup data then seek the one requested by the report.

Here is some of my code used:

''' <summary>
''' Use to hold the Appliance Lookup BO
''' </summary>
''' <remarks></remarks>
Private _ApplianceBOLookup As New Business.bizAppliances
''' <summary>
''' The first time this property is used, it will check the 
''' lookup BO count > 0 if not it will load all the records
''' Then will use the BO.SeekToPrimaryKey to speed up finding
''' the description value.
''' This method is much more faster than using a Custom Field Property in reports.
''' </summary>
''' <remarks></remarks>
Public Overrides ReadOnly Property [ApplianceName]() As System.String
     Get
          If _ApplianceBOLookup.Count = 0 Then
               _ApplianceBOLookup.FillAllRecords()
          End If
          If _ApplianceBOLookup.SeekToPrimaryKey(Me.FK_Appliances) Then
               Return _ApplianceBOLookup.ApplianceName
          Else
               Return String.Empty
          End If
     End Get
End Property

With the above code the time to render the report was reduced from 37 seconds to 3 seconds.  I still need to figure out how to create my own class to implement the IRenderSite, but know that the report is rendering as it should, I will have more time to get that done.

Here you have a sample for the IRenderSite:

http://www.perpetuumsoft.com/ForumTopic.aspx?lang=en&topic_id=356&forum_id=9

Thanks for the link, I had downloaded this project sample before, but it did not work for me.  It is in C# and it is generating 2 compiled errors, which I believe are caused because the project was created for an old version of RSS.

I posted a request for a new sample from them, so let's see.  Thanks anyway for keeping this in mind.

Anyway, I used Trent's report sample and added a RenderSite class to it.

Hope it helps.

Thanks a lot for taking the next step and provide the sample.  It is clear now how it is done, without the sample and the poor help file it would be very difficult for me to really understand this.

Now I can have my own WinRenderDialog wich looks more professional and in synch with the application's look and feel.

Thanks again!