If I understand you correctly:
aufpassen; would go in cell 1 (substitute a semicolon for a colon)
Pass auf!: Watch out!, 6 would go on the next line in cell 3 separated by a colon
Passt auf!: Pay attention!, p. 8 would go on the next line in cell 3, separated by a colon
All the runovers would be in cell 5
As to your other question, this gets so confusing! I would suggest moving 'aussehen to look like, to appear' to the next braille page so that its subentry is in the correct place for this entry word. It does leave some extra blank space at the bottom of a braille page, but it makes it clearer for the reader.
As information: BANA is working on wording to clarify all of this in Formats - as well as putting together a guideline that is a separate document regarding FL. Stay tuned for that as I hope it will "fix" a lot of your questions relating to these sections.