First you open the professional report designer and scroll down to the section Beahaviour in the Property Grid. Then you choose Visual Basic as a Script language.

 

Then you insert a rich text element and go to the Property Grid. In the section Behaviour you open the dropdown list Before expression under Scripts and click on New:

 

 

Then the Script View opens. There you enter the following code:

 

Private Sub richText1_BeforePrint(ByVal sender As Object, ByVal e As System.Drawing.Printing.PrintEventArgs)

Ctype(sender, XRRICHTEXT).LoadFile("C:\\Dateien\\TestRTF.rtf")

End Sub

 

In the parentheses after LoadFile you enter the path to the rtf-file you want to load. The path should be in the following form:

 

drive:\\folder\\subfolder\\filename.fileextension

 

Then you save the report. You successfully loaded a current RTF file.