Menu numbers

I have a presentation with 1 scene and some slides.  In Player Properties / Menu the menu is ordered as:

1. (Scene Name)

1.1 slide

1.2 slide

1.3 slide

etc.

If I delete 1. (Scene Name) using the red X button and choose to keep the items children the menu now looks like:

1.1 slide

1.2 slide

1.3 slide

etc.

How can I get the menu to look like this:

1. slide

2. slide

3. slide

All of my presentations have a single scene.  The numbering of slides as 1.1, 1.2, 1.3,... doesn't look right.