On-Page Scripting Paragraphs
Putting a newline character (pressing enter) breaks the on page script, but you can just substitute them with HTML break characters instead. <br>
Add more or less to get the desired spacing (I use 2).
If you're using the Rich Text Editor be sure you are adding it as HTML (does RTE still have a source button? Click it if it does).
Pagetext & Page Script
Another thing that can give similar results is using $PAGETEXT, which isn't on-page scripting, but goes on the page script (haven't tried with link scripts, don't think it'd work there).
i.e.,
$PAGETEXT := "Added at start. " + $PAGETEXT
$PAGETEXT := $PAGETEXT + "<br>Added at end."
Starting Page Text:
This is a new page.
OUTPUT:
Added at start. This is a new page.
Added at end.
:= means assign to, while = alone is for comparison. I know I forget the : sometimes, which breaks things.
Because it is in page script, you can add variable conditionals before $PAGETEXT changes.
i.e.,
IF %BLANC = 0 THEN
$PAGETEXT := "He is dead."
From what I recall, you can use newline characters here (without HTML) but you do need to escape the double quotations. & q u o t ; = ". (Drop the spaces between & q u o t ;, because I don't know how to have it not be read as HTML but written in correct form and am too lazy to google it).
i.e.,
$PAGETEXT := "& q u o t;Watch out!& q u o t; he yells." + $PAGETEXT
NOT ""Watch out!" he yells"
I'm sure you can see how this can be tedious, but if there is minimal or no dialogue, it can be worth considering.
Tips and Tricks
Replacing spaces with breaks (for on-page scripting) or quotations with their entity code (for page scripts) makes proofreading harder, so I advise writing normally (but clearly marked) in another writing software. This can also act as a backup. (Word has a search and replace feature, for example, which makes replacing quotations easy). But do whatever works for you.
Do be aware that text added through page scripts doesn't start on the page, so isn't counted towards the length calculations. If you write the whole story this way it'll be marked as 0 words, which is funny. Considering you're probably using this for similar but different permutations of the same scene, I find it evens out, where it lets you avoid artificial bloat to the word count (from copy pasting many similar pages, which is another cruder option). Depends on how you structure things.