This is not an online Eidtor issue. It's about HTML List Rules.
 
First let's make a test.

 

Type the following HTML code into the FrontPage (if you installed it on your machine):

 

test<br/>

test<br/>

test<br/>

test<br/>

test<br/>

test<br/>

test<br/>

 

Select the first line and click the order list.

 

You will find out FrontPage has the same behavior as Cute Editor.

 

The <br> tag is a special HTML element, not a Block-level element like <div>, <p>

 

Like other editors, Cute Editor implements the IE MSHTML Editing Platform.

 

One of the general rules for what happens when you click on a list toolbar button:

For selected paragraphs that are not list items, make each paragraph a list item.

 

I know it's a bit tricky when intervening <br> element. The users may want the editor automatically remove <br> elements; And also want the editor add a list item between each <br>...

 

>>* ps for real XHTML support, <br> tags are represented as <br /> tags.  Does the Editor understand this?

 

Please check this example: