Downloaded OOO320m18  on Mac running Mac OS 10.6.4
installed
created a new spreadsheet
copied a 2 col x 40 row (approx) segment of a staroffice spreadsheet
that had a few empty lines near the end  (because staroffice would not
let me write (save) it--I hoped OO would work better)
pasted into OO at 2nd row, 2nd column
clicked in left margin (row numbers) to select 3 (empty) rows near the end
of the newly pasted in content
clicked to get menu, selected "insert rows"
now the numbers in the cells are no longer displayed aligned with
the grid of boxes, as if the data got its font size increased without
increasing the box size
and there are no new rows in the area expected.