measuring 9 yudim
This is a mezuza written according minhag chabad. The chabad custom is to leave 9 yudim, both after uvshearecha and before vehaya. The problem related here is relevant also to shiyur parsha in a sefer tora. How do we measure the 9 yudim, [compared] against the line below or above? I think we should measure against the line above, bein lekula bein lchumra (although obviosly lechatchila the 9 yudim should be recognized against the line below as well, but that is not me'akev). This may differ from a revach parsha pesucha which is at the end of the line, and revach parsha setuma [according Rambam] that is at the beginnig of the line [9 letters before vehaya], there the measure should be both in regard to the line before and after.