Homepage content element – Recent Listings – Grid display leaves blank cells

Directory Theme 8.8

The Recent listing Content Element on my homepage is not displaying well.
I have it set for 5 listings across (but this problem occurs whatever the number chosen) and the first two rows of listings are great.
Then things go a bit haywire! see image.

There are missing cells – not missing listings, just that cells are not filling.
Any ideas how this might be fixed.

Also, is there a way to limit the number of rows in this feature? What is the default and how many pages does it expand to?
All suggestions welcome.
Many thanks.