Why can't I merge all cells within a row?

This was not a problem before I updated Numbers this morning. Previously, I could copy a set of rows from one Numbers doc, and insert into another Numbers doc. The copied/inserted rows contain no divisions at all while the rows above them do, but the formatting wouldn't change. Now, when I copy the same set of rows into a doc, the formatting changes to match the rows above. Why?

Secondarily, why can't all cells within a row be merged? I just want a simple row with no divisions into cells. Can anyone help?

This is what I could get it to look like:

Now, this: