Same on my Mac. Using is the traditional html way.
Here's a neat trick you can use whenever you want spaces to be kept.
Define a new formatting shortcut, say 'n' for non-breaking space. (Settings/Configure Formatting Codes)
Give the new code a meaningful name (NBSpace)
Give it a unique formatting code (n)
Opening HTML is <style>p {white-space:pre;}</style>
Closing HTML is empty
Click Hide content from Live View/Preview
To use this, at the beginning of the first line of your custom slide include this
{n}{/n}
If you put that on it's own line, you get a blank line.
In fact, you can put {n}{/n} anywhere in your slide. It doesn't have to be at the beginning, although that makes it easier to see what you have done.
