When I forget, the entry I had to change to get paragraph spaces to show in the Manticore WP theme:

}
div.entry-content p{
margin: 10;
padding: 0;
}

The original values were, for some reason, both zero. I did try a margin of twenty, but that didn’t seem to make a difference. Zero to ten did, but ten to twenty didn’t, and neither did changing the padding value. Oh, and now the break tag has no effect, though it did yesterday, and that has nothing to do with the CSS because it did that before the edit. Go figure.