Why does the graphics screen not show properly when F10 is pressed in edit mode?
This is the visible result of a corrupt PCK file. If you have a backup file revert to that. If not make a note of or printout all the parameters in the setup. Rename the existing PCK files (REN *.pck *.old enter). Start the software and a new PCK file will be created. Check that graphics now work ok and then alter the parameters to match the originals. Take a backup copy of the PCK files for future use!