Answer:
You have probably defined different colors for the screen display and the printout report.
Open the "Display Properties" dialog box using the RFEM/RSTAB menu "Options → Display Properties → Edit". Then, you can specify the appropriate settings of the screen and the printout report for each category; for example, for cross-sections (see the image).
If both representations should be identical, it is necessary to select the For screen and printout report option in the "Identical Settings" section first. All entries subsequently made in the settings then apply equally to both the screen view and the printout report.